Then something is not right.
The master cylinder is somewhat suspect as it is of unknown quality and build... It may have been marketed as a "direct replacement, exact fit" but that does not mean it is the same size piston with the same travel and the same lever to piston fulcrum dimensions as stock.... just that is was advertised as such. But it is what it is, so rule out other issues first.
Id start with cleaning the rotor, then hitting it with a refinishing disk, then cleaning it again.
Pads can be cleaned, sanded , cleaned and be 90% as long as not oil contaminated...but never really come back fully if they are contaminated at all IMHO.
Wrap some Teflon tape around the bleeder nipple threads...and re bleed the brakes with a hose on bleeder nipple in to clean jar partially filled with brake fluid so you can observe if you are getting air out of the line. Also change the orientation of the Master cylinder so the return port in the fluid cup is at the highest point.... you will get some trapped air to come out that return bleed port many times.
Check wheel bearings, no slop...
A rebuild of the caliper is a good idea as well, pop the pistons out and i bet you find crud in the bore that did not come out with a bleed.
clean well and install new seals which need the designed elasticity to work right and old seals even not leaking ones are commonly a source of brake performance issues.