Star Firebird-L (FL) This is significantly more overstable than the Stalker, handles a headwind very well and powers down beautifully. Again, this may be more overstable than you're looking for with a healthy fade at the end, but if you need a wind-fighter or something with a dependable fade, this disc is a beauty.
Saint Pro: Again more stable than the Stalker when new, very similar to the FL, but lighter weights aren't as stable and they lose quite a bit of stability if you deflash them.
Gold Line Saint: To me this is a bit of a longer River. A tick on the understable side, go heavier opto for more stability. I recommend this disc because it was the first longer driver I could throw well and at a variety of speeds. This disc will power down beautifully.
Fuzion Escape: A tick more stable than the Saint. I prefer Lucid plastic myself or Moonshine for the most stability, but even in Fuzion I found these to be just a hair more stable than the Saint. This is a strong contender to best fit what you're looking for. It's like a longer Stalker in my book and can handle lower power as well.
Neutron Volt: Probably my second favorite disc after the Escape. Very similar. A little turn, a little fade, a lot of glide. Handles powering down. Very useful for a bunch of lines.
Top recommendations: Escape or Volt, depending on which feels the best for you. If you want something with more stability, check out the FL.