I've always had an affinity for Helm. I'm one of those weirdoes who loved playing Clerics, even back in the 1st edition AD&D days, and Helm always struck me as the quintessential cleric god (along with St. Cuthbert for Greyhawk.) There's something about the devotion to duty I've always admired, and I note he was the only deity whom Ao found worthy of retaining divine status during the Time of Troubles, and set him as guardian against the gods returning after they were cast down, a duty which he fulfilled even though it pained him to do so. I always felt he got a bad rap in the fallout from Mystra's death...
My first cleric I ever played was an AD&D 1e cleric of Helm, and I always remember playing him fondly.
Tymora is the other deity from FR I like most, just because she is the quintessential god of adventurers. It could be said that Cayden Cailean from Pathfinder Golarion is the "Tymora" of Golarion -- she was the archetype for the 'adventuring deity.'