Sounds like you're on a buying run. The small, inexpensive kits are great fun, as long as you have realistic expectations for them. They can sound real good.
Drums reach the point of 'diminishing returns' fairly quickly. There's a bit of a noticeable jump going from the least expensive to the next step up. After that, in most cases it takes more of a discriminating eye and ear to notice the differences. The small kits like the Safari/Bop are great bargains, and can fill a lot of roles.
Anyways, about the small kits. I tried converting a 16" tom into a bass drum, but found it just a little too small for my liking. I'm real comfortable with an 18" bass though, and 20 is the largest I consider going with nowadays.
I'm really adjusting to a 4 piece too, after always using 5. Just a bit of a difference when doing fills, but of course the basic timekeeping grooves (hats, bass, snare, ride) will be the same.
A while back, there was a big surge of people buying the Safari/Bop kits. I wonder how many still have them?