Vanilla sex relationship in need of some spice.

I'd encourage you to continue experimenting and trying things out. My wife and I used to go weeks without sex and what fixed it for us was making time for kissing, cuddling and talking about sex, but without pressure on either of us to 'perform'. It also helped when I realised she was naturally very submissive and needed me to take charge in the bedroom. I've had to go quite slowly as she tends to freak if I put things in BDSM terms, so initially it was more about me taking control verbally, the odd spank etc. I started by massaging her, then tying her up while massaging her, 'torturing' her with a feather etc. Maybe your OH would be happy to do that? Vanilla people can freak at the idea of 'hurting' another person so gentle stuff works best at first.