Siege

Alright, I haven't played any RTS games seriously since back when Starcraft came out. I agree that there pretty much is a set template and the difference b/w games is the units/spells. But here's my take.

Resources- My opinion is that you NEED resources in a game. If you don't, you REALLY will have the horde mentality you mention. Why? Because if everything is free, why don't I just keep throwing things at you?

In terms of progress, what kind of progress can you make with only a certain amount of unit base? Let's say John and I play Starcraft. I'm given 10 marines and he's given 5 zealots. What's to say what is progress? Should it be based on kills? It can't be, because if I manage to kill one of his zealots (or he kills one of my marines) One of us is already faced with a clear disadvantage. One of us has made progress in terms of kills while the other one will have even more difficulty making said progress. Should it be based on time? Again, this doesn't seem logical. We're going to be playing this game equally, so when I hit the 10 minute play time, so will John. If it's discovery of the map, the answer becomes "choose the race with the fastest units." In terms of effectiveness, going back to my Starcraft example, the only effectiveness you can have with a limited unit base is based on combat. Do I get extra units because I can micro manage my marines better than John does his zealots? If that is the case, this becomes a problem, because if the AI suddenly decides that John did an AMAZING job of micro managing, he could suddenly have a ridiculously large army and overwhelm the game. As for the fickle whims of the forces I represent. That is MUCH too random (which is why they're fickle I suppose). If you make such a large decision completely randomly, that takes out a lot of the strategy. The strategy soon becomes "the race that makes the best decisions consistently vs. the race that either gets 1 unit or 1000" and hoping for something in your favour. While your suggestions are good ones. I don't think they will work if you can only get units by receiving them as opposed to building them. Or it would help if you could tell me a little more about what you want to suggest.

Personally, my solution to resources is to make the person you train also a resource. If you want to train a marine, you'd better have a civie who can receive said training. Or else tough luck (or retrain some other unit. But that's way too complicated.) If you have an ever growing population, then you constantly have units to train. But this solutions has some BIG flaws. Which I won't go into unless someone wants me to.

Fog of War-

This seems like an easy way to get rid of micro management. Micro management is difference between an average player in RTS and a good player. If you make it that an avatar of yourself MUST be at a battle for you to take command, that severely limits your ability to micro manage and what happens if that avatar of yourself dies? Do you automatically lose? If you decide to go out and battle in an opposing country, and your home country is invaded. You won't be able to micro manage your defences. Realistically speaking, every army should have a general "managing" your forces anyway. So why not make that general the player him/herself? If you don't like the idea of enemies knowing about you, go out and kill his scouting units. The key to RTS is to know what the enemy is doing, while at the same time not letting him know what you are doing.

Horde Mentality-

Again, I will use Starcraft, since it's the best reference. Let's say John is Zerg. According to your theory, John should mass Zerglings. This strategy is HARDLY undefeatable. The terrans have their firebats, and the protoss have their reavers. Yes, reavers are mid-late game units. So let's think more early game. If I know that John is simply going to overwhelm me with trashy units (which I should have a clue of, if i've done my scouting properly), then John's strategy is to have those 200 or so zerglings beat the living hell out of my 30 or so zealots. Well, zerglings can't fly. And any respectable tournament map has choke points. Why wouldn't I build a few zealots to be meat shields, have some dragoons and some photon cannons? All these units/buildings are easily attainable by the time John has a respectable amount of zerglings. And to be honest, I won't need very many zealots/dragoons/cannons if i've done a good job selecting a good choke point because not all the zerglings will fit and the cannons/dragoons will tear up the zerglings before a decent amount of zealots are all destroyed. Granted that John can wait til he has the transporter upgrade. But without the speed upgrade, the overlords aren't going anywhere without getting shot down. But by the time he has that, I should have at least 3 reavers up and running. I don't care how many zerglings you have. 3 reavers properly micro managed with even a TINY support force will destroy HUGE amounts of zerglings as long as I have the minerals to buy scarabs.

Now to be honest. Marines really DID fall under horde mentality before Brood War came out. The zerg didn't really have a way to deal with them effectively. Stim packed marines were cheaper, and better than hydralisks. That is why they introduced lurkers. As long as there is an effective area-of-attack unit, horde mentality shouldn't be the dominant strategy.

Difficulty-

I won't talk about the difficulty section, because it seems you are talking about the single player side of the game which I don't really have a solution for either. I'm more about the multiplayer side of games.

I'd like some comments on my take especially from the thread starter

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