Radisson Lyon
Hello,
We stayed at the Radisson for Valentine's Day (or week-end, actually) last year and found it great ! The location is very convenient, right by the Part-Dieu train station, and the panoramic view is amazing.
This seems to be mostly a business travel hotel so they had a week-end deal at 99 euros / night compared to 249+ euros normal week rate (IIRC).
Cheers,
J-