So now you get 500 down & up through PPPoE with VLAN?
My ISP asks for a MTU1500 so I set the PPPoE interface as such. I dont know your providers specifics, but MTU1492 could do fine.
Yeah, this particular r28346 24.10_snapshot is good with a rockchip commit and luci patch that removed implications. It benefits rockchip devices over RC5.
I don't know how to expand your internal eMMC storage, I have a model with no eMMC. Good luck!