Leave record size at default. Or set it to 1M. If does not matter. Leave compression enabled. Unlike other filesystems, zfs does not waste space. In orher words, if record size is 1M and file is 5k — it will take 5k on disk (roughly).
(If you are referring to block size for various SSDs in your pool — set it to 4K when adding with ashift parameter. But since you mentioned default 128k — it’s a record size. I’m not sure why did you put it in quotes there. It’s actually called record size and has very little to do with device block size)
Generally don’t change any zfs defaults unless you have a very good reason to (I.e. measured and proven bottleneck). The defaults are designed to work well in vast majority of circumstances. Storagenode is not a substantial workload to exhibit any bottlenecks on common hardware.
You may want to review this thread Notes on storage node performance optimization on ZFS