In DDO we've seen the creation of Prestige Enhancements to take the place of PrCs in PnP. There's nothing wrong with this idea, but I have a concern with the way they have been implemented.
Prestige Classes are NOT based on specific classes! At least I can't think of any examples that are. All of them require some combination of the following: BAB, feats, skill levels, or caster levels.
There's two things to note about this. One: You only take one prestige class, and two) what you take along with your base class(es) is only limited by your imagination and the pre-requisites. Examples: Tempest is not a Ranger prestige class! In fact, it is easier to qualify as a fighter. Arcane Archer, in addition to the race limitations, REQUIRES arcane levels, whereas in DDO there is a serious disincentive to MC your ranger. This limits choices.. if I had a nickel for every Tempest Ranger on Thelanis...
Another DDO problem is stacking weirdness. You could conceivably have FOUR prestige enhancements lines - three classes up to level six, plus Arcane Archer (elf) if you could afford all the feats and AP.
NOTA BENE: This is not about any particular feat or class. I don't care about bow strength or STWF. This is purely about structuring Prestige Enhancements to capture the flavor of Pen and Paper Prestige Classes in a DDO way.