It depends on the system you run. It's funny that this was the "year of the PG in the playoffs" at the start, with all the talk being about Billups, Rondo, Rose and even Brooks. But by the conference finals only Billups was left and the rest were Mo Williams, Derek Fisher and Rafer Alston.
BUT: we might not NEED a star PG, but we do need a PG who is just a bit better than Blake at:
1. Ball handling (he's easy to press)
2. Defending speed (he's "scrappy". Like Scrappy Doo. Everybody hates Scrappy Doo.)
3. Feeding the post (Rudy is much better, and Rudy is NOT a PG)
4. Imaginative passing.
So, if Bayless is Jarrett Jack on Steroids, I want Blake on steroids. At this point in his career, Jason Kidd is pretty much that (except for the defending speed part). I was hoping that Koponen could be that - and while he's better at most things than Blake, he's rather turnover prone and he can't shoot.
As many people have said, Fisher is designed for the triangle. In the Triangle there isn't really a PG, but you do need competent passers at all positions (which is why the Lakers are much better when Odom plays than when Bynum plays).
But fuck it, do you want the Blazers to be boring, or do you want them to be the Suns with D? If the answer is the latter (and if it isn't, you're lying) then you need a star PG. I really really REALLY hate the trope of "we don't NEED a PG because ROY is our PG" because he SUCKS as a PG. He's a great PG for a shooting guard, but if he was our full-time PG we would break all records for slowest pace since the shot clock era. He WANTS to be our PG, but everybody thinks they're a PG, and most of them should be politely told otherwise. Don't make me bring up Larry Brown-Allen Iverson-Eric Snow again!