If you want to try a wine yeast, get one that ferments maltotriose like Lalvin K1-V1116. I think it's a killer yeast though so I wouldn't co-pitch it, although you'd have to check that out as I'm not completely sure
Nottingham is the fastest dried yeast with good attenuation, belle saison has the greates attenuation but is a bit slower. If you are fermenting low as you say, then you could co-pitch these two as you won't get off flavours from notty and the belle saison should take the gravity right down in a week or two
That does sound like a good plan, combining Nottingham and belle Saison. I read a bit about Nottingham and it looks like an attenuation of 85-90% is possible with low mash temps. If the Saison yeast is then even cleaning up a bit further, there shouldn't be much left to feast on for the bacterias.