Re: Not being challenged as Uke?
When it comes to the ikkyo pin (or ikkajo... you do yoshinkan?), I have trained in places where they definitely manage to put it on so that it hurts and you need to tap out. However I don't think this is usual. I would say it is normally just a pin, and it is meant to immobilize but not necessarily cause pain. I think whether you tap when you feel you have been immobilized or not depends on the dojo and the style.
I certainly understand where you are coming from when you say you are not feeling challenged as uke. I have trained at a number of dojos, and at some of them they didn't particularly focus on ukemi, and they weren't used to training with people who were reasonably flexible and could maintain their balance. I think how you approach this depends on the person. Some people love the challenge and appreciate it when you can help them polish their technique. Others get frustrated and annoyed at you for "messing up" their technique. I find that with the latter category it is often better to just grit your teeth and fall over or tap for them. It is still frustrating though.