What is he eating for solids? Make sure he's getting enough protein. Beans right out of the can are great (well - rinse and drain them first; they're full of sodium, otherwise). They're so cheap, and they're so easy. Kids especially like kidney beans. Take the usual precautions against choking.
As for weaning that middle-of-the-night bottle: for all I know, there might be a reason not to wean him off of it just yet, so I won't assume that that is the goal (check with the Dr. Sears Nighttime Parenting book; you can probably get it for $5 for a used copy on amazon.com). But if the time is right, and he really is ready, definitely don't make him cry it out. Cold turkey is not the way to go, unless you somehow secure his participation (I don't recommend bribes or pressuring him to be a big boy). Like a rite of passage ritual. Make sure hunger isn't the issue first, of course!
My two pennies. Hope they help.
L.