I don't see the problem with bottom lane.
Sustain loses to burst: Soraka loses to Blitz Leona. Her heals mean nothing when you're bursting with ignite.
Burst loses to Poke: Leona loses to Janna. Leona can't initiate when she's at half health.
Poke loses to sustain: Janna loses to Soraka. Soraka's team initiates trades and then recovers.
The real problem is that top lane is run mainly by guys who can sustain themselves infinitely. Shen/Udyr/Irelia/Vladimir/Kennen.
Sona slaps Blitz around like a two dollar whore, can't speak about Leona.
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"What I'm saying is mind over matter only works when there's not much of a matter to mind. " - Lopen
The Cult of Personality.