I think you’re going overboard if you make a dedicated fixture for this size batch. If this is a common batch size for you, or might be in the future, I would suggest that you invest in modular fixtures.

However, don’t design a modular fixture system from scratch – there are trusted systems on the market. I’ve reliably used the Halder V70 T-slot system, but if you’ve generally got smaller or simpler parts, you could probably get away with the V40.

I agree, buy yourself a modular fixture system – it’s worth the money if you will be doing more mid-sized batches. I prefer the Witte ALUFIX as it’s just far more flexible. Setting it up sometimes takes a bit of time, but it’s more capable of handling complex geometries. There are some youtube videos showing different examples of how to set it up, which will help you to get the hang of it.