yeah i was really impressed on the print quality from a USD 280 3D Printer

the bad quality on the rear, where all the filament is bad and misaligned , was because my glass was not secured correctly with painters tape ... i had a woobly glass and that was funny to watch for sure , but not funny at all after i discovered that eheh . so while printing i added some more tape to secure the whole thing
i think adding melted PLA from the nozzle on the top of the case will do th trick but it's pretty risky, also, i can fill with some paste ( i dont know the word in english ) you know this past that is used on the walls to fil gaps . then paint the case . but i never done this before . so it will be totally new experience for me .
i already heard about acetone vapor but never done it too . i think i have to test this on small parts first
for the side finish, i think using small grater will be ok but i think apply correction to the model to allow the edge to be more visible could be a solution to this . i think apply acetone with soft brush can be done this way too but never tested it before . Ad far as i know, pla is does not react as the ABS reacts. but to verify that , i have to test it before