Downtube shifters are an acquired taste; you'll get used to them (and use them with more alacrity), but you might not ever completely like them. Options are bar-end shifters, or thumb shifters for friction derailers. for indexed there are also the brifters, but we've covered that briefly.

Saddles are, even more than shifters, by far the most personal of bicycle components. I find Brooks leather saddles comfortable, from the first ride; that's not the common opinion. Good ones tend to be expensive, whether old-style like the Brooks, or one of the technologically advanced designs. You'll find that some people will disagree, being completely happy with a bargain saddle that just happens to suit their derrière to a T.

Keep riding, and don't change too much at one time.