I am definitely a fan of inexpensive (relative - not the scary cheap ones i expect will spontaneously burst into flames (im kidding)) lipos.
I am almost always looking for the thinnest C dimension on HK. So that i can have two in series (2 * 3s for 6s, or 3 * 3s for 9s… etc.), but keep them “low profile”. Better clearance, less visible and more stealth, and still relatively easy to charge vs one 6/8/9/12s battery.
Personally i’d skip the BMS for lipo and use the money towards Li Ion, or better/more lipo’s! add BMS later, or just pull them to charge normally w/ iMax B6ACv2 or similar charger.
a BMS is extra weight and complexity that gives you 0 additional miles. that same $/weight in lipos/li-ion = more miles!
ESC vs VESC - i’d usually decide based on the voltage/#series batteries you want to run. Most hobby RC ESC’s will max at 6s. Some will do 8s (usually pretty $), and a few will do 12s (usually more $ than VESC). I like the ability to run 12s. So either DIYes 12s ESC, or similar, or VESC would be my suggestion.
Fun scenario… you have a 12s BEAST, and your buddy/friend/enemy ask to ride it. Always want to spread the stoke…so of course you hand it over … and it’s promptly crashed w/ them on their ass…
or option B - take the board, flip it, pull 1 or 2 batteries to give them 6s power, and hand it back for them to try. It’s not a sofware “newbie mode” like i love on my Marbel, or on my buddies boosted, but as close as i can get today…