May I ask, how is S2 a worse company than Riot? They engineer their game based off of what people want. The reason why HoN is not doing as good (but definitely not going down) is because the community is fool of elitist jackasses who make the game unfriendly for new players. Also it's not free (which is changing soon).
You say LoL is the "best option" for the MOBA genre, but doesn't that apply to how people like to play the game? If competitive, HoN has a way better competitive community than LoL with: advanced UI including guides, active replay functions, HoNcast.com for study of professional matches regularly. If for fun casual play, LoL is much more friendly to new players, much more new, refreshing content than DotA and it's counterpart HoN, as well as a level bases to manage skill gaps (even though you can create smurf accounts but farming IP keeps that down). Also I don't think LoL's community will dwindle based on DotA 2 considering it's taking the same physics type, style and game play from DotA/HoN making it as completely different from LoL as HoN and Dota are. The lack of Riot's compassion toward their community will be this game's end.
P.S. HoNs competitive scene is actually pretty bad now. Honcast used to be good but is pretty unprofessional now (I watched them when they went to dreamhack during beta) and with this most recent dreamhack I'd say riot was far better (even though they had a ton of disconnect problems which I believe is unacceptable.