I think it can be wise to use these batteries for some powerful headlights (if you’re a night rider)… Otherwise not entirely sure, mixing could be an option but I have not personally tested this yet
By mixing - combine it with more powerful cells. Info is lacking but perhaps you are willing to take up this challenge and once and for all see and witness does it work or not… been reading / seeing a lot of posts with opinions about it (mostly by not recommending it) but practice should show the truth…
Second option - get more laptop cells! There are people running ebikes and even EV’s (cars) with them… you just need plenty of them, for 6s pack you probably need at least 10 in parallel, I think, if youre able to fit a such large pack, it may work… If the discharge is higher, say, 2.5A per cell (which would stress the regular batteries, I believe), then you could get away with about 8cells in parallel pack, so 6x8 = 48 laptop cells.
Try to harvest as much as you can!