Haven't had a successful print in mnths, looking for new printer

About a year ago I received a Creality K1 and it has been acting up over the past few months. I got it used from a family member who I know takes good care of equipment, but I think it's just old and ready for retirement.

Six months ago I replaced the entire extruder assembly with a Creality one, and it worked fine for a month. After that it basically shredded the plastic gears inside it, so I replaced them with metal gears. Now my prints just aren't sticking to the plate. I've tried glue, a textured plate, different plate temps, and even printing at super slow speeds. Nothing has worked, and all my prints fail at the first layer, with buildup around the nozzle.

I don't want to get a new printer if it's not necessary, so any advice is helpful. Feel free to ask questions if clarification is needed.

If worst comes to worst, what would y'all recommend? I'm hopefully looking to get out of Creality, maybe BambuLabs. Max price about $500, similar print size to the K1.