To answer your question, for the most part, unless the street noises are significant, they are not going to make much practical difference on room correction since the volumes used in correction will still be significantly louder.
Speaker size: unless the speaker has a very large radiation area, the size does not matter significantly, except to make them hard to place, and some speakers are better with more distance to allow for driver integration.
Room correction is an attempt to fix things that are wrong ... and just that, an attempt. It can help, but not a panacea, with the systems that take readings at multiple locations being better but again not perfect. How much work are you willing to put in?
People look at room correction often thinking mainly bass, but they actually work better through the mid-range up to their limit, say 5-8KHz. At higher frequencies, the speaker (on and off axis) dominates alone what you hear, and room correction can attempt to compensate for anomalies in the speaker response that reaches you, but still an attempt.
Down in the bass frequencies ... under a few hundred hz in a typical room, the room and where the speakers are in it is everything. At a given position, frequency response can jump up and down 10db. Room correction will soften this, but not fix underlying issues. You are better off getting RoomEQ, Arta, etc. and measuring at your listening area while moving the speakers around to get the flattest response in the base, and then using room correction to fix what is left ..... or take the next step and learn about bass traps, absorbers, diffusers, etc.
Room correction is often better than nothing at all, but not as good as doing it properly.
