I've not caught many pitches, but I am aware that few a) Want out regardless on 31st October (or before), no extensions, b) Are prepared to go no-deal, although some are wishy washy enough to suggest they'd leave it on the table (unused ?) c) Have no intent to push May's anti-Brexit deal again with or without hoping to fiddle around the edges, d) Consider prorogation, & e) Rule out further referenda on Brexit and general elections.
Doesn't leave many acceptable candidates left to impress us on other issues and push their unique selling point.