All the tech doesn't mean much when accoustics are completely hampered in a vehicle. Why go in the great outdoors to listen to music???????? That I will never understand! Like these guys who watch tv and play on their phones.
Anyway, individual solar panels which are almost always 36 cells in series should have a min of two internal bypass diodes to be safe in shaded situations, more diodes means more output when shaded but they try to get away with as little as possible because this is weekend warrior territory. Good roof mounted panels usually have 4-8 albiet usually higher voltage (more cells in series per individual panel). 2 diodes and heavy shading may still degrade these cheapo panels overtime, but my guess is after the warranty, the have alot of flexibility as many can't easily recognize a panel that is not right. None have int blocking diodes because such things are not really needed and would add to the costs. They can serve to stop other parrelled panels discharging into a sick panel. But in certain cases you might get some action, like one panel facing the very early morning sun, and the other facing the complete opposite dark sky, the darker panel may well have a low enough voltage.
If shade really is a problem, then best not buy a store brought package, as all those individual modules are in parallel themselves.
Fwwi, when you parallel multiply 12v lifepo4s , the junction containing the positives attains the same voltage across it, so they all act like a big battery with SoC equalizing, and the currents drawn will be shared equally (if cables are fairly balanced). The bms should have a temp cutoff on the switches but I doubt that much is being drawn.
On my lithium battery what I do is set "the floor" to around 12v under load (which is close for small loads and fairly large) when that point hits, my victron BMV reads 0% SoC, giving me a tiny reserve for house keeping. 15-20% SoC is my reserve tank. With my AGMs I use to take them to 80% DoD to get my money's worth on such heavy weight (two 120's).