Consider Before You Buy Your First E-Bike

Actually there is a lot to consider, there is also the option of a front hub motor but when it comes to hub motors then the choice of motor itself, like a geared motor or direct drive, or you can also get the beneifts of direct drive in a geared motor being the GMAC which can get you regen. You could also go mid motor powering rear rear instead of the crank, you could also go hub motor as a mid drive.

Price is a factor yes, but the biggest factor is what kind of terrain you are riding, the slope grades and how long they are, do you want reliability or do you want light weight or do you want heat shedding capability large mass dd's. If your riding back country you dont want to many things that can go wrong, like to many moving parts that need to be lined up like 2 chains and gears.

Deciding factor for me is
#1 what power levels do I want which includes #2 top speed, from that comes your battery voltage/discharge choice and controller selection to match
#3 the kind of motor setup, for me, usually direct drive
#4 price
Everything after is just fine tuning like do you choose a programmable controller, do you choose a sinewave foc or trap/square wave controller, do you want regen
Choice of bicycle is important so I'd put that at #5 unless you ride technical then it would be #1