Sounds like a numerical overspecification. 0.1% voltage measurement accuracy is hard to reach reliably, or will be expensive, and won't deliver any benefit whatsoever regarding SoC estimation or cell life. Since li-ion capacity and lifetime is limited by the cells and specifically cell cost, build a lower-cost BMS and use the saved budget on more cells, to build a better performing battery (as a whole).
Another example, 2A balancing current requires careful thermal analysis, heatsinking design, will add clearly non-zero cost and weight, while provides no benefit whatsoever, unless your packs are truly massive (1000Ah+?). There is a reason why commercial BMS's tend to limit to around 0.2-0.5A, and why I designed mine to balance at 40mA, using an intelligent algorithm dividing the balancing time instead of brute-forcing it.
I would try to dedicate all efforts primarily to make they system as robust and fail-safe as possible (simplicity is one of the keys), and secondarily, study (by literature research, or own measurements) which mechanisms are important for cell aging, and which aren't. This depends on the actual cell, as well, so it's best to choose a few you "support" best, and study how they perform.
Example points regarding robustness:
Look for stuck-on balancing, possible heat generation and thermal fusing in worst case firmware/logic failure.
Example points regarding cell aging:
Tapering charging current before the CV voltage may easily increase the cell life by 10x (say, from 100 cycles to 1000 cycles), with only small impact on total charging time.
Similarly, adjusting charging current based on temperature, or heating/cooling battery properly, may easily increase the cell life by 10x (Say, from 100 cycles to 1000 cycles). And no, this may mean you need to heat the battery above room temp, instead of cooling, in certain conditions.