I feel like I'd need both of these. If I can't hug my waifu there's no point, and if I can't communicate with her there's no point. I just need her to be cute (not necessarily realistic, just cute) and feel good (not necessarily realistic, just good) and to be able to communicate on at least some level.
Cute and warm with advanced enough AI and clever software and hardware design to make me feel like its love is real. Cute and warm is easy. Cuteness is practically free, that's just art design. Warmth will come from the internal parts. If anything, they'll create too much warmth and that will be an issue. But with clever heat distribution perhaps you can spread the heat throughout the body to make it feel like realistic (or pleasurably unrealistic) body heat.
The AI then just needs to be able to keep up a basic conversation. It doesn't need to be perfect. The trick is to make the personality acknowledge it's a robot but one that has just a tiny spark of humanity and strives to be more human. It's a classic sci-fi trope for a reason, it's super endearing. When her AI makes a mistake, now it is justified, and she can become frustrated over it or something, which is then cute.
I also figure bipedal walking is a problem. So I advocate having her AI acknowledge this as a disability, and then she can use a wheelchair or something. The trick is essentially using "story" to get around limitations. It only needs to be good enough to make me feel like it's real.
It's not about realism, per se, but about verisimilitude.