Without stripes I doubt spinners will be able to saturate 10Gbe anyway... Maybe if every client hits a different physical drive and there are enough drives and clients. That's over 1GByte/Sec... There are few enough SSDs that can sustain that in single drive configurations. Some nvme can do it.
With a remotely modern card, jumbo frames are not needed and can cause all sorts of problems with other gear that can't deal with large MTUs. I don't bother. I tried it with a point-to-point network, it works, but CPU use didn't change more than a fraction of a percent, throughput didn't change much more than that.
CPU for the network isn't a major issue with most gear, at least it doesn't seem to be for me. My old 1366 based server handles it without noticeable load. ZFS uses more CPU than the network does. My cards are old connectX2s, nothing fancy.