Devorgilla
I think Labour and the other parties should put forward candidates. This is very different to standing aside when the previous holder had been murdered. The electorate should have a choice of candidates and it's up to them to decide who to trust.
In theory, I agree with you, but in reality, there are constituencies where people don't have any choice. I live in one of them. The Tory MP has a majority of over 27,000 and she's useless. I can't see her hanging on to that majority in the next election because she's not that popular, but she'll still win.
If we were placed in the same situation as Paterson's constituency, I think there would be an appetite for voting for an independent (probably centre right) MP. I'm not sure Rory Stewart would be independent enough, so somebody with a reputation for integrity but not connected with a political party would be needed.
We already have a district council run by non-national parties after the Conservatives were defeated in most areas.