Hey, after all you`re creating this game, so if it`s unstable, than you`re the one to improve it, and if it runs slow, you should just think about optimizing it. Usually you try to find a way around, not give up.
1. You can use .md2 models with up to 500-600 trigs each.
2. You may draw the healthbars for a short time, after an unit is hurt and hide it after that. You can make 10 texture healthbar images, each showing 0, 10, 20, 30 and on health and use it as a billboard image above the unit since you`re showing lots of them at the same time, and the eaxctness of your unit health is not that important- it doesn`t matter if your unit is say 36 heath and your healthbar shows 30 or 35.
3. You can use "fog of war" to hide totally what`s not seen and on...
4. Use a plane with animated texture to represent water and on. You may change that anytime if you have enough fps.
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