If the power and resume LEDs flash alternately, it usually means a board-head pairing issue. The new logic board and print head need to be matched via service mode reset using Canon Service Tool v5100 or higher. Without that, the printer will not register the head ID.
It depends a lot on the print volume. For those who print occasionally, refilling still makes sense. I switched entirely to compatible cartridges from Cartridge Save about six months ago and haven’t had any reason to go back. I use them on two Pixma TS5150 printers, and for photos or detailed...
I have the PRO-310 and it's easily the most consistent pigment printer I've used. Nozzle switching works as advertised, and the Chroma Optimizer really helps with gloss papers. It finally feels like pigment printing without the usual headaches.
Had the same issue when testing glossy RC papers on Canon pigment models. The coating is not optimized for Canon Lucia inks. Try a true Canon Photo Paper Pro Platinum or Pro Luster. The difference in adhesion is huge.