I've assembled the parts to do a major upgrade on my old Ender 3pro 3D printer. I've got a touch-screen display, a 32 bit main board, a BL Touch auto-bed-leveling kit, metal extruder (never had any problems with the stock one, but while I'm tearing it apart, why not?) and an official lighting kit.
I almost certainly would have been better off buying a new printer (and I may yet) but I learn more by working on this one, and that's part of the fun.
I have the same model in a similar situation. I let mine sit too long which means largely starting over. I think I might have to replace the extruder because the existing one is hopelessly clogged.
Like you, I thought a little about replacing it. For what I paid for this in 2020 I could have one that does multiple filaments and self-levels and lots of bells and whistles. I'm opting for trying to get this one running out of Calvinist self-flagellation as much as anything.
J. Steven York RESISTS
Dave Slusher - SFFH