This thread was real interesting to read.
I have to agree with JC that sloppy is a negative term when it comes to playing music, and if you play sloppy, please be kind to the rest of us and keep it in your garage. Sloppy means you do things you shouldn't.... drift in timing or put notes where they don't belong in the musical context at hand.
That said, I agree with muddy that traditional salsa context can be confining (although there's much legit syntax available to those who know the language). I think if your time is dead on and your drumming works well in the jazz and experimental contexts, freeform and expressionist are much better terms to describe you style....
back to the original KingKongas point.... here's my approach to soloing:
riffs that come back into the rhythm are lots of fun.. they add variety and taste to your music...and most teachers should be able to get you going on a few.
but since I perform primarily for the entertainment of my wife and dog... I often like going into longer soloing runs. For those I recommend asking your teacher to show you various phrases common to afrocuban soloing.... don't worry about putting them together and don't worry about fitting them on the music.... yet.
Next step is listen, listen and listen some more.....until you're really familiar with the style and definitely at least until you can comfortably come back in at any time, in time and in clave with the rhythm "official" pattern.
Lots of great recordings out there that'll demonstrate how the soloing phrases are used by the great, and you should be able to at least nail down how things sit down tempowise.
So for now, until you can count 16 bars while soloing (which is pretty darn difficult in my book), you can work some soloing over the music... and because you'll know where the rhythm is you can end it with a short pause, a couple of filler notes to finish the bar, or going into a riff whose ending point is known to you.
Hope this helps.... have fun!