I think the enemies should be something you have the option of using biotics or tech on. ME1 had heavy Geth, and very few organic enemies, comparatively. ME2 has the Collectors as the main enemies, with varying sizes of mechs throughout. They even took out the need to have high electronics skill to hack safes.

If they could do it without it seeming spoon-fed in a pre-mission cutscene or something, that'd be nice.