Unless you are using perfectly and properly Matched, Batched & Binned cells (provided with cell test reports) you will have issues with balancing & runner cells. No Joke, plain & simple.
Using the 280's which are popular right now:
* The Matched cells all test out between 282AH-292AH and their IR & Impedance is identical or very close throughout their entire operating range, whether charging or discharging.
* Bulk Commodity cells typically test between 270AH-282AH and their IR will diverge at the hi & low end of their working voltage rangewhich most often presents as Runner Cells which will reach cutoff point well before the others within a pack. Put THAT into a Parallel config and thing get whacky... There IS a lot of unhappy experiences with that noted through the forum (and people don't like to admit they goofed, so many more not mentioned).
There is little to gain and you lose some reliability by building a pack with parallel cells... These are not EV's with 3.5AH Li-Ion cells that are severely tested, matched & batched. If it is to save bucks on a BMS, it's like roofing your house with paper only. It really is not the place to save chump change. Your batteries, equipment & life are worth more than that.
Honestly, the best approach that allows for Load Sharing (reduced system stress), failover in the event of failures / errors and the fault tolerance that comes from that.
3 Packs of 16S in Parallel will split the Discharge load between the 3 packs as well as charge input. (will charge same as if one pack)
Each pack if setup properly can handle the full Charge / Discharge capacity in the event of a pack shutting down.
THE ONE GOTCHA !
With packs in parallel, it really does work well and you can expand the bank if/when needed or wanted. BUT the lurking gotcha.... Assume you have 3x 280AH packs in parallel and want to add another pack. Another 280 would be perfect obviously but if the new pack is much larger / smaller the potential for odd things happening increases, generally if less than 100AH difference it's not bad because the voltage curves are such, it really isn't an issue. If greater than 100AH difference, then you'll get premature cutoffs and such when at the edges of the voltage curve, pending on BMS, this could cause the lower AH cells to draw from the higher AH pack. It can be dealt with but requires fusting and planning.
BTW: With large capacity LFP cells like we use, Passive Balancing is not very helpful because the cells are so big and passive balancing only burns off power from Hi Voltage cells. Active Balancing actually transfers power from Hi Cells to Lo Cells and some can do up to 10A (Not Cheap). I myself use a QNBBM-8S on each of my battery packs. I have 2x 280AH Bulk cells, 1X 280AH Matched & Batched, 2X 175AH Used EV LFP packs (which I was going to mod into a 350AH but the parallel wall hit)
REF: QNBBM Active Balancers by Deligreen:
https://deligreen.en.alibaba.com/productgrouplist-806516208/QNBBM_Balancer.html?
Hope it helps, Good Luck.