All non-oral routes, not just patches, are easy on the liver as estradiol bypasses it and has much less effects on hepatic parameters such as coagulation factors, proteins, renin substrate and triglycerides. The higher the dose though, the greater the effect. Overall though, bio-identical estradiol remains quite safe, even at higher doses, according to several studies.
On injections, my levels fluctuate significantly, at 2,500 pg/ml on day 3, down to 1,300 pg/ml on day 5. APTT, a test that can apparently predict the risk of DVT, has come back normal, time and time again, despite those high levels.