K., you are doing every absolutely perfectly! It's ok if he still wants the formula every 2-3 hours -- that's quite normal at this stage, and formula should still be his primary source of nutrition until he's a year old. You can start adding more solids, maybe give him a vegetable AND fruit for lunch and dinner. I would also offer the solids between meals, and not immediately after a bottle. In addition, I gave my son water in a sippy with his meals to help "wash" them down.
My son is 19 mos now, and he still eats every 2-3 hours, even though he's not on formula. He usually has meals and then snacks in between each meal. So this is similar to what your son is doing, and will continue to do, if that makes sense? My daughter (whose name is K., btw!) is now 6 mos, and she is on two solid meals a day, but she still probably takes up to 30 oz of formula per day, and I generally consider her formula the primary source of her "meals."
Anyway, pats on the back -- you're doing everything right. Continue to follow his cues and your mommy instinct, and you won't go wrong!