Compost is much easier in quantity and wormeries are a bit like keeping hamsters. Fun at the start but soon becomes a chore and a bit fiddly for the results you get.
I know what you mean about outdoor heaps and rats, though, so I compromise by using my Council wheelie bin and a collection of plastic dustbins after drilling plenty of drainholes in them. Despite all the dire warnings about not composting food waste, absolutely everything goes in mine and the lids keep any vermin out.
Worms will last as long as there is food for them and it doesn't get too cold/hot/wet/dry. They won't go near citrus either, so no orange and lemon peel. IME you get much better activity if they have somewhere to retreat to i.e. they are on soil, in which case I would go for one of those green Daleks with a lid.