I recently received and updated the R5C based on the firmware selector. I did find that opkg was not included with the snapshot, but updated/upgraded and installed luci using apk add
Model
FriendlyARM NanoPi R5C
Platform
rockchip/armv8
Version
SNAPSHOT (r28146-52b6c92479)
As of now, at least for the R5C, 24.10-SNAPSHOT still seems to have opkg whereas snapshot already has apk. That was my finding over the last days but might be subject to change.
If you want to switch to the 24.10 release when it comes out, the most logical choice would be to go for the 24.10 snapshot.
If you don't, then the normal snapshot makes more sense.
As I can see in owut it will be possible to set rootfs size directly in image.
I don't have owut available to install on snapshot so thinking of migrating to -rc4 and to stable later on.
I had no issues with 24.10rc2 on my R5C gateway and 24.10rc4 has been running without issues for 4 days handling CAKE, VLANs, adblock, and https-dns-proxy for my network.
I've used the firmware selector to include packages in my downloaded squashfs sysupgrade firmware updates. I do not have experience with owut, but plan to give it a try at some point.