You gotta remember that, potted with a huge copper pill or not, in the end it’s a tube light. The main heat bleeder on it is the hand that holds it. It’s not a problem for me, since I rarely use the S2 I have on a mode above 20-ish lumens (1%).
I’ve made a spreadsheet roughly estimating the current, lumens and runtime on a 3400mAh battery, but can’t post it right now that I’m on mobile. What I can tell you for sure is that the 35% mode on a 4*7135 will be a pleasant surprise for you at 0.49A or so. For 0.1A, you’d have to spring for a 3*7135 and put it on the 10% output.
Biscotti is exceptionally flexible - you have a variety of mode groups in all flavors to pick from, with “moonlight”-ish or so (0.1) reaching 50 at most, to full blast every time, to down-ramping. Memory and blinkies are equally optional. A flowchart can be found in the Desert Tan S2+ thread. I myself haven’t had much use for anything but mode group 8 (0.1%›1%›10%›50%) on a 7135*8 M1 and a 7135*6 S2, but I don’t use either too too much. On a thrower, for example, an overall more powerful mode might be preferable – maybe once I get off my ass and learn soldering, a driver swap on my C8 might tell me the answer 
For the discount, just shoot Simon a message through the Ali system and he’ll adjust the price. I often do it because I pay him through PayPal, going around the AliExpress route.
I’m completely inexperienced with messing around with electronics in general, let alone flashlight modding, so I feel your pain. lol
