Nice pics
>cells from 1600mah up to 3400mah in a single pack to get 258Ah per pack.
Yes, this is OK as long as the packs have the same total ah / pack. There are other factors that may affect things a bit such as IR.
@Wolf has done extensive work and shown (among other things) that IR can really fine-tune pack performance.
Just sharing - not *strongly* pushing....
I have built 84 packs at 260ah each so far - pretty similar in capacity. I didn't pay detailed attention to IR - just added up cells / pack to get same ah. I've found that after putting them in operation, I needed to tweak about 10% of them by adding a few cells (and in 1 case, disabling 2 cells).
What happened is that 10% of the packs seems to sag a little (in comparison to the other packs) during the charge/discharge as they operated - so I started adding a few cells to help smooth things out. Some packs needed 3 cells. Some packs needed 6 cells. Its a slow process over several weeks to make this adjustment - e.g. add 2 cells, use a hobby charger to balance it in better, and wait and see for a few days. The repeat the cycle - till daily balance not needed on any of the 84 packs.
Because of this, I personally leave room to add some cells per pack + room on the shelf to clip on a few cells with cell holders/alligator wires on top of each pack. Once I have them perfectly tuned, the cells are permanently added to the the physical pack in the empty slots.
I use Batrium - so I can turn on/off balancing + its heavy duty balancing which made it easy to see the packs. You're using Chargery - which will have balance on all the time but very slowly on 258ah packs... so it could be a month before any patterns emerge depending on how aggressive your daily charge/discharge cycle is.