Why is it that there appear to be more different nuschaos of Selichos than other tefillos? I have heard of Askenaz, Sfard, Lita, Polin and Ungvar.
Selichos is a prayer service that was not formalized until late in the Gaonic period. This means that there was already greater geographic diversity before any of the prayers were established.
Before the gaonic period, only the viduy and 13 middot were 'required'. This is different than most other tefilot which already had a basis before the vast dispersion of Jewish communities.
The first b'racha before "Sh'ma" in the morning has
I don't know how many of the possible combinations exist in practice, but that's just one b'racha (and I haven't listed all of its variations!): I have no reason to think there are fewer nuschaos of shacharis than of s'lichos.
Perhaps fewer nuschaos of shacharis have distinct names assigned by publishers than nuschaos of s'lichos do, though, and if so then I don't know why.