what do you do most?
Bottom line is: If only owning a quiver of one, the answer depends on what do you plan to do most, river running or creeking? If mostly river running, then a Diesel, Hero, or Burn would be spectacular for that and some creeking. If mostly creeking, then get a creek boat (Habitat or Rocker as examples). Since you're just transitioning towards either for teh first time, I would encourage you to the river running design first. Not many people are skilled enough to jump into the consequences of creek boating without having run a lot of IV and V rivers first. As you probably are aware, creeking is extremely dangerous. Additionally, I think the Diesel, Hero, or Burn are some of the most excellent boats ever. You would likely be having great fun in one for a long time.
No risk, no reward. It is not that we have to, it is that we get to. Preparation and education are essential to self-confidence and success. - KV
"If there is no risk there is no adventure."- Bill Briggs