You are on the right track here, in every regard, though BUN and creatinine are related to kidney function, not liver. Think of your kidney as a filter, The test will determine how well your kidneys are working, based off the amount of muscle enzymes have passed through it, into the blood. But this test doesn't take into account that someone with more than average muscle mass and someone that is training hard, will have more enzymes than a normal non-athlete. Sounds like you understand that and yes, the best way to get a better reading would be to go without lifting for a couple of days. Still, I would expect it to be a little higher than normal if you have some muscle. The key is to keep an eye on these levels and test often enough to see if the levels are stable or rising. If they are high, but stable, this is one thing. If they are high but still gettting higher, this is a red flag.
As for your cholesterol, sounds like you are planning some good options to fix this. Go with your plan. Fish oil, healthy fats and foods with fiber like oats. For this, as well as liver and kidney function, yes, the key is taking time off. So often, you hear these young guys saying "I'm ready to go back on because I don't feel shut down anymore". Recovery is so much more than just testosterone levels. The only way to recover and stay healthy, is to come off and give your body down time.
As for your estrogen, this is what I would call crazy high! Get on the adex ASAP. I would start with .5mg ED for a wk, then drop back to EOD