So your basic issue is it's difficult to navigate between the activating the "Light attack" skill and whatever TP skill you're trying to use. I've never tried, but can't you move the "Light Attack" skill? And even if you can't, wouldn't them changing it to allow you to move it solve that problem? All without the need for an AA.

Because classes are always going to have "super" skills that do more damage or have effects, there needs to be limiting factor on how often you can use them. As you mentioned, they can either do this with TP or with Cooldowns.

So you say you don't want FFXI's boring, "wait pressing no buttons until I have 100% TP", but then you go on to say that you actually do, just in different words. If we keep the system as is and just allow you to move the "Attack" button to a more convenient location, we arrive at the same place.