I think you can control the overdraw by sticking to shapes that fit well inside of a triangle and keeping in mind how it will tile. I'm not saying it will work for everything but it could work well in certain scenarios, specifically with particle FX where you have more to worry about than just tri count, birth/death,…
Something like that^ Depending on the particle type you could get a few particles on each tri. You can get creative with the texture and the sheet to utilize more of it. With them swirling around and churning you probably won't notice that 4 particles are moving in unison. The same trick can be applied to bushes and leaves…