You can use prop or TNE...both are best pinned ED, but with prop you can do EOD. TNE should be ED. I always use it up front until the test e/c starts to kick in. Same thing with the deca....I'll use NPP ED until the deca starts to kick in. But yes, the test prop (or TNE) is a great idea and I always use it. With the TNE...I actually will run it after the longer ester test kicks in. I'll pin it about 2 hrs. before my workout on workout days, and be a madman in the gym. A little HALO or drol can't hurt as well.
As for your liver, abusing it is sooooo over rated. You would be surprised how much of a beating that thing can take. I would not worry about it at all....still, use milk thistle and Liv52. You should really consider running the NPP along side your prop or TNE to help get the ball rolling faster. Some also do this with tren. Start with tren enan AND tren ace....and than stop the ace when the enan kicks in. But because I feel tren enan is the devil, I will never touch that stuff ever again....that stuff is beyond dangerous. Take too much, and you are FUCKED!! But with short esters like ace, sides go away in a few short days...unlike a few weeks with enan. And don't forget to run some HGH along side your cycle....those new muscle cells that split need to grow, and since you are using deca, I wouldn't think twice about not including HGH in your cycle (and it will help you recover much easier at the end as well....just continue to run the HGH for a few more months). It will help keep your gains, and make you harder, drier, and more vascular. Good luck!!
/V (and thanks for posting your stats)