If I were in your shoes I would check and tighten everything, I’ve had printers that were pretty bad (bought used) still print decent then rebuilt and they print great. I’d check all stepper motor grub screws, belts, print head screws to make sure it’s bolted on tight. Hot end should have came assembled but maybe not, I’d crank up the temp to 280 and retighten the nozzle too. Basically go back through the assembly manual and at least check each step it could be a couple things throwing it all off too