I absolutely hated that aspect of UD3's takedowns. It absolutely does not represent the reality of high level wrestling. There are many ignorant amateur wrestling coaches that tell you that you need to just try harder (represented by the twirling control stick). The reality is that you have to try hard and be mentally tough in everything you do in MMA from takedowns to striking. Ultimately it's a matter of correct application of technique and timing. The best wrestlers are both loose and explosive and often they will abandon a takedown attempt if they feel they are going to get buried under a sprawl and instead transition to other continuations or adjust the direction they are driving. If you are having to "struggle" (as seen in UD3) it's because you are making poor technical choices.
In regards to the main topic, I think differentiating the input for defending clinch attempts and takedowns would help a lot.
In addition I would love to be able to feint takedown and clinch attempts. This is a very legitimate strategy in real MMA.
And there should be an animation associated with failed attempts at denying clinches and takedowns