For the food transition, my only recommendation (which I didn't heed with my first kid) is to try "Baby Led Weaning." I know Chic is a strong proponent. We did traditional baby foods with #1, and it worked fine. Eventually transitioned to regular solids. With #2 it was too much of a pain to try to spoon feed him food while we were all eating normal meals, so we decided to try BLW and just give him what we were eating (with a few caveats - low sodium, non choking hazard, no honey, etc). I've since become a BLW proselytizer. It was just so much easier to eat meals together and it helped him try a lot of foods from day 1.
In terms of having a third kid, I feel like we're almost ready to close the door, but are having trouble being definitive about it. Still have all the clothes and most of the stuff (although did just give our infant car seat away to someone who couldn't afford one). But we have a three bedroom house that fits our family well, it's easy to get a table for 4 going out to dinner, and we'll always have the right number for amusement park rides ;-). Not to mention the fact that #2 is simply more of a hellion than #1 ever was (he's 16 months) and the thought of another one of him is exhausting.