The argument has been touched in another post, so after a few games this are my impressions about the units in beta4. Overall I think they're much more balanced than before, but some units are still much weaker than others. I'll divide them into four categories:
1. units that I buy if I don't find them in an amount I feel correct. I regard these units as tendentially under priced or balanced.
2. units that I use only if I find them, but I never buy them. I consider these balanced.
3. units that I pillage or keep depending on the situation. I consider these mostly balanced or slightly overpriced.
4. units that I pillage on sight. I consider these as overpriced or needing a rework, because sometimes I wouldn't buy them even if they cost less or much less.
=========== 1. Units that I buy ==================
Scout : I buy it sometimes, for UL or if I need to travel through desert.
Light Infantry : it's a very good unit to start with, and you can then buy something better in that city without losing much.
Orc : I buy it depending on the map and the position. Probably under priced (maybe 200).
Elf : it's probably the best 1-turn unit and I buy it almost always. Probably under priced.
Heavy Infantry : I buy it mainly in 1vs1 or when I expect to meet the enemy soon, otherwise I skip it.
Dwarf : I usually buy it, but moderately
Pikeman : I buy it sometimes, depending on the position, but much more rarely than elves.
Yeti : I find it always worth to have, to make your Dread Knight more powerful.
Wizard : a great unit, I buy more than one if I have the money. UL on them makes them too powerful, imo, because they're so fast.
Scorpion : if I have the money I buy them, at least 2, less makes no sense. Potentially they're the strongest 2-turns unit.
Kraken : very powerful on sea
Sea serpent : rather low priority, but it can give you a great advantage. I wouldn't underestimate it.
Other units that I buy, usually in this order: Red Dragon (or Pegasus), Devil (should be a 5-turn unit imo), Pegasus (or Red Dragon), Grand Archon (also 5-turns), Green Dragon, Medusa (rarely).
=========== 2. Units that I use only if I find them ==================
Crow, Eagle
Heavy Infantry : excluded the cases above.
Light Cavalry : I'm still not a big fan of these, but when I find them I'm not unhappy.
Wolf Rider : good unit with a lot of possible uses, from morale to critical strike, and they don't burden your finances.
Crusader, Giant, Heavy Cavalry, Minotaur : other good 2-turns units
=========== 3. Units that I pillage or keep depending on the situation ==================
Battering Ram/Catapult : you don't need these as before, since now negative bonus is plentiful and makes them less useful, between the two the battering ram is the one I've used the most. I usually keep the first and pillage the others.
Ghost : at the beginning of the game I tend to pillage them, always in 1vs1. Otherwise, once you have a good lot of them, they're good.
Unicorn : depends on the mood and the situation. To have to wait 4 turns for one of these makes me skip them mostly.
Mammoth : if there's a lot of ice they're obviously fabulous. Otherwise a good unit, but sometimes I like money more.
Medusa : since there are Yetis that are also faster, they've lost a bit of appeal to me.
Sandworm : they aren't a bad unit, very useful sometimes, great on desert.
=========== 4. Units that I pillage on sight ==================
Spider : too slow for an attack unit, and HI is better to defend towns. A town with wall 10, 2 HI mean 25*2=50 STR, against 45 of the spider.
Gryphon : even worse, because it's a flyer and a 3-turns unit.
Elephant : I saw somebody using it, imo it's a waste. I'd plunder them and get a dragon instead.
Archon : no thanks. I get his bigger brother. If Grand Archon were a 5 turner I'd consider them.
Demons : they were an amazing unit, now they're a pain if you have them, because it means you didn't pillage them. I'd like they were just as they were before (+1 attack and ignore city walls, now that elves/wizards are more common and there are also eagles they were already a bit weaker, but still good for sneak attacks).
Elementals : I rarely consider keeping them. They're a bit overpriced maybe.
The problem of raising the cost for some units (Dragons, etc), is that people who find them will have a big advantage, so I wouldn't raise the cost too much, unless maps were modified, to prevent spawning of these units.
Another problem with units balance (plundering vs keeping) is that neutral towns that produce (sometimes not really) good units produce 4 kinds of units, often all powerful, so it's almost always better to pillage them, sometimes even if it's a dragon. With the proceeds you can sometimes buy whatever you like. I'd like better if neutral towns produced only one unit, unless it's determined through 'detailed production' in the map editor.
Even if neutral towns produced by default only one unit, to reach a balance among units is important to me because players who find units that are worth to keep have an advantage over players who find bad units. For example, I find a town with Medusa: hard to kill, not always worth to keep. A town with devil: hard to kill, well worth to keep. One with dragon: relatively easy to kill with elves, good to keep. A town with ghost: a joke to kill, a lot of money guaranteed. A town with spider: hard to take, and then you plunder it. If I find myself surrounded by medusae or sandworms, and my opponent finds all the good stuff and easy to kill, victory is a question of luck.
This aspect is maybe impossible to solve 100%, in maps with random city production, but a better balance among units would help because the advantage of plundering vs keeping wouldn't be extreme.
Compared with beta3, 1 turners have been toned down (good thing) and 2 turners are sometimes worth buying and almost always worth keeping. 3 turners are still very weak overall (except Pegasi and Kraken), I would give 3 HP to Elephant, Sandworm, Gryphon, Elemental and maybe Medusa. 4 turners are either too strong (Devil, Grand Archon, I'd make them 5 turners) or too weak (unicorns, I'd make them 3 turners with 2 HP, and demons).
Some changes I'd like were:
Slighly lower price for some 2 turners (Crusader 650, Heavy Cavalry 600)
Minotaur : 25 + 10 in city (still cancellable by unicorn, but a bit stronger), slightly lower cost (650)
Spider : 15 STR + 15 in city, move 16, 2 of the following : critical strike 20%, ignore city walls (they climb them), swarm (+2 up to +10); cost 800
Gryphon: STR 35 + 10 in city, 3 HP, 18 move, cost 1000
Elephant (900), Sandworm (950), Elemental (900) : 3 HP
Medusa : 3 HP, or 2 HP + critical 100%
Unicorn : 35 STR, 3 turns, 2 HP, cost 1500
Devil, Grand Archon : 5 turns, cost 2000
Demon : STR 30, +10 attack, ignore city walls, no swarm, 3 HP, cost 1600
It would be nice also to have some crossed bonus between units, that come in place only in case of individual combat (as for anti-air), for example:
Fire units: elementals, red dragons, devil, demon
Fire vulnerability: spiders, scorpions, battering ram/catapult, mammoth, yeti(-5 against fire units)
Fire resistance: dwarves, giants, sea creatures (+5 against fire units), fire units
Ice units: mammoth, yeti
Ice vulnerability: fire units
Ice resistance: units with fire vulnerability, sea creatures
Creatures of Light : elves (-1), archons(-3), unicorns(-3), crusaders(-2) (-x to creatures of Darkness in individual fight)
Creatures of Darkness : orc(+1), wolf rider(+2), ghost(+2), devil(+3), demon(+3), medusa(+3) (+x in fight against all creatures, except against creatures of Light)