Asking a very few (who'll answer) on here is not a good way to do your market research Matt
If it helps though, I know quite a lot of Wedding togs and NONE of them use an external editor
Due to software advances and computers being quicker too I, and most of the togs I know, can edit their own photos in around a day's work, meaning we all have plenty of time to do it if we are full-time Wedding togs; I suspect those requiring editing companies will mostly fall into 2 types
1 - those who are new and don't have the knowledge/equipment to do it themselves, and
2 - those who are working part-time and just haven't got the time spare, but who are also less profit sensitive as they have an additional income source
As you already know the market is saturated with those in poorer countries offering editing at incredibly cheap rates, which I'm guessing you can't (or more likely don't want to) compete with
If there is a higher paying market for editing I suspect that'd be portrait studios where they'd be wanting a more 'fine art' editing style, something they can't do themselves or at least do it quickly enough to make it work; maybe developing a small range of high-end editing styles would suit you better where you'd charge by the image and deliver something as a big printable work of art
Sorry I can't help more but I hope this is useful
Dave