I think the main problem with Generals is the Idol system. The only cost of the unit is the manna which is quickly regenerated at the crystal, thus all minion related strategies involve running back and forth between the crystal. Sure, you have to buy the Idols in the first place, but after that you just spam the summon button. Because minions technically don't cost anything right now, you cannot make them very powerful. If each unit had a specific cost then they would be far more valuable and you could make them much more useful.
Of course, gold is already scarce. Thus I would imagine that the economy would have to be reworked slightly. However, I think it could be done rather simply. You could either give Generals an additional resource soley for gaining units, or you could give Generals a way to increase their gold income. Remember the references to QoT's Money Tree in the hidden Beta 1 files? I think that would be the best option. The additional gold would be balanced as the Generals would basically be required to buy units in order to have any combat effectiveness whatsoever.
Once this is the case, the Generals would purchase units directly instead of Idols. This way each unit would actually have a cost. Again, they are currently limited due to the fact that they are essentially free via the health crystal. They can't be too powerful because they have no real value. If you give the units a specific value, then you can make them much stronger in accordance to that value. Then the power can scale with the cost of the unit.
I would also like to see some more unit types. Not that much, just enough to give you some options. We have melee troops which are pretty straightforward and the Siege Demolishers that work as both ranged support and anti-tower. Personally, I would like that to be split into Archers and Siege troops with the siege troops being more expensive but outranging towers while Archers have less range but are also more economical for common use. Priests are good as they are. Angels would be great. They would be perfect for projecting your power across the map, and low level angels would be good scout units.
Giants would be nice to have. If they kept with the four unit variations like they have now, then Lv.4 Giants could bring some serious pain, similar to Experimentals from SupCom. Actually, there's a lot of stuff you could do with giants. Instead of having four levels, have four different kinds with different abilities. There's the standard giant, the ranged giant, utility giants with abilites, giants that can capture flags, etc... Kind of like bringing a sub-Demigod onto the field. There's some cool stuff you can do with a high level summonable unit if you want to get creative. Even just standard high level giants would be a lot better than nothing.
I'm OK with special minions working as they currently do, as those are supposed to be special. I would rather if QoT and Sedna had a different method of summoning them, but I guess it is tolerable. I like the Oak and Erebus's methods of obtaining units.
The thing is that this wouldn't be all that difficult to impliment. The hardest part would obviously be the extra minions, and I honestly don't care so much about those. Even so, the base units already exist. Some visual modifications would be all that is necessary to get them passable. And I don't think what I'm asking for is outrageous. I just want the basic unit classes that already exist in the game to be available to the Generals, and I would imagine that they would be implimented in a four-level system similar to the current idol summons.
But again, I don't care so much about that. I think it would benafit the game, but other things take priority. If nothing else, just get rid of the Idols! I think that the Idol system is preventing the game from being an RTS. Just get rid of the Idols!!!