Most Helpful Guy
I think you're already on the right track. If you both agree to having a slower pace and finding a more intimate connection beyond sex, then do that. Make sure you're both clear about what you want as you want it. You can't be sure he'll know what you want if aren't willing to be a little vulnerable and vice versa.
He's already admitted he'd be open to something serious, he's just being noncommittal in speech because he's looking for concrete signs of trust and commitment from you first. If he knows you heat up fast then taking things slow is the trust exercise. Hang in there for a bit and if things get better for you then push for more physical intimacy and full commitment. If not, then hey you tried.