We had Wee dragonauts, kiln fiend, and now nivix cyclops.

Although it has defender, it stays out of bolt, defends confidants, revokers, snapcasters, thalias, factories (most things outside golems, tarmos and robots-oath guys). A bit slow, but could deliver a great blow itself
There is another guy that bumps for direct damage (but less relevant imho), and niv-izzet elemental. Blue and red are my favourite colours, and this is a fun idea, thought probably not a good one. I had some years ago some success playing dragonauts in legacy, maybe those little izzet critters can grow into some trouble.