soprano or tenor

Tenor probably offers more opportunities unless you are interested in playing soprano in quartets.

In general, alto, tenor, soprano, bari would be the order of acquisition I would suggest.

Tenor is the easier horn to learn for most.

I second Tenor.

cool, thanks!

There is no objective answer to your question. It depends on you, not the instrument. DAVE

If you want to know the easiest option, it's to stick with the alto you have. Otherwise, I'd decide on the basis of what I'd like to sound like, and then face any problems when I came to it.

I second with potiphar and Dave Dolson.
Soprano and tenor are just two different instruments!
Are you in love with Mary or with Cynthia?
In Both?... So, take 'hem all!

Obviously it's a personal decision; however, many commercial settings (wedding bands, Rock Bands, Horn Bands) utilize tenor 90% of the time. So if it's a matter of working as a saxophonists - getting a quality tenor set-up is a priority.

With that said, I enjoy playing soprano WAY more than my tenor.

Tenor

it's the best jazz sax that there is... In my opinion.

Why not learn clarinet or flute and become a real doubler?

Interesting, I have a tenor and soprano and am going to try out a friend's alto for the next month or so. (Not that I'll be adding a new horn to my collection any time soon.)

I play in a local, small-town blues/rock(ish) band. I might play the soprano for 3 tunes throughout the evening even though I'd rather play it closer to 50/50. My band mates would beat me silly if I played it more. (Mind you, they do like it in our version of King Bee and The Weight. They tolerate it when I occasionally use it for Hoochie Coochie Man. After that baseball bats are retrieved from concealed bags...)

I guess you'll have decide who you are playing for the most (be it you, bandmates, or an audience) and go from there.