If you think level 1, 4, 6, and 10 abilities are the "top-end" abilities, you are DEFINITELY in the wrong genre.
Cross-class abilities are not the solution to a basic entry level class rotation that can't even run.
What I consider the bare minimum of occupation you consider spamming. This is your top gear. This is my 2nd gear. I expect conservation as a strategy to employ tiers of output, one of which is not standing there. You don't expect that.
I expect the same things you do. You just seem to want lower-quality forms of it.
Then why are you spamming them in your rotation? Clearly your rotation fails since you can't manage your TP, and you aren't even using top-tier skills. Perhaps instead of constantly ramming your fingers on 111111222222233333222222444444, or whatever your order is, you should actually take a look at your TP, take a look at some of your other skills, and go from there. For instance, did you realize you could equip Internal Release from pug, which grants a 20%, 15s crit increase on a 60s CD? So basically, you could set yourself up for your mass-DPS rotation, throw on internal release and spam your highest DPS rotation. Then when it's over, you'll most likely need to cure up, so you could either cast Cure from conjurer, or pop second wind, and go to your lesser TP rotation.
Instead of just constantly spamming your attacks at a furious pace, you slow down a bit, give a second or two between each command, and let your TP start to accumulate (or at least not drop more). Then when your minute is up, start it over again.
Or if you are tanking, apply the same idea but replace internal release with something from gladiator, like flash, or convalescence, or something. Throw in more abilities that consume less TP, but offer other buffing/debuffing/healing effects.
The whole point of cross-class abilities is to provide you with a means of better manipulating a weakness of your character. If that happens to be TP regeneration, use those abilities to frontload your damage and then you can ease off when they aren't up. Not everything has to be a spamfest like you seem to think. Again, that's not a strategy, that's just mindless number mashing.