As a protoss player I'm obviously going to tell you to play protoss. Although I should probably tell you to play terran because that's my best matchup... nevermind.
I used to play zerg but the macro was just too difficult so I switched to protoss. I like protoss for the following reasons
- It's easy to get whichever tech you want because they all branch from the cyber core
- It's fun watching a couple units wreck an entire army
- They feel the most strategic to me, the other player is generally trying to adapt to the protoss, so the protoss has to predict and force the opponent
- Although a pain while microing, warp gates are easy to macro with otherwise
- I enjoy tactical micro, and that's what protoss has. Terran has a lot of apm micro, whereas protoss is very positional and based around abilities like force field and time warp which don't do actual damage but are still hugely important
- you can play either very aggressively or defensively and be successful