I'd give him a shot over Ashton.
I question whether he has a long term future as an international but, as you say, we need to get a proper look at him. This summer (/this Autumn) are the perfect opportunities to have a look at some alternatives.
I know there are question marks over a couple of back three players, but we do have a reasonably settled unit. We could trial Wade there, and if he doesn't work then drop Nowell/Watson straight back in, no drama.
Also, I've read that Daly wants to become a first choice kicker at Wasps, rather than long distance. They'll need one with Cipriani arriving next season, but it also just adds something else to his case for England.
Be interesting to see whether he sticks at 12 going forwards. Manu is flitting between 12/13 for Tigers. I'd like to have a look at Farrell/Tuilagi/Daly at some point, with Slade on the bench covering 10/12/13.