Issues with prints Ender V3 SE

[Psycosis]

Just started on the 3d printing journey and am having a few issues, hoping someone can help without me wasting too much filament.
I am changing between different filament which probably doesn't help too much, but these are some of the issues and hopefully someone can point me in the right direction. I haven't tried the same print with both types of filament to compare, as it might work better with the standard PLA

I bought a PEI bed as the stock one was terrible and things would stick so hard, I struggled the remove them.
I have run the calibration for temp, etc, and put those settings into the printer.
PLA bed-60c and extruder-205c
PLA+ bed-75-80 and extruder 220c

1. I am getting corners lifting on some flat prints, where items are supposed to be flat against the print bed, this is using white creality PLA+ filament. I had the bed set to 75c and the extruder temp to 220c. Not sure if either of these are too high. The brim also has come lose on various prints. The edges or overhangs look nasty too, all lumpy, see the cube also.
IMG_0479.jpg

2. I printed an infinity cube, and the top looks nice, but the underneath looks terrible. Edges aren't square, corners are lumpy, the pins that link each square are great and smooth on top, but look nasty on the bottom. This print didn't need supports, but it looks like the filament hasn't fused properly?
IMG_0473.jpgIMG_0474.jpgIMG_0476.jpg

3. I have some issues with prints either not sticking well enough and coming loose, or sticking and then i get a spaghetti mess on top. example photo, took 4 tries to print, changing settings over and over to make it work. I want to try to remove these issues. I got it to print eventually, but it was more luck. There is supposed to be a clip in the middle of the circle, its very small and that would come free. I ended up making a brim and got it working, but the last two still had an issue with that turned on, really late into the print.

IMG_0480.jpg

[Bikeracer2020]

I never print PLA, but I think that it needs 100% part cooling fan right from the first layer, perhaps check part cooling in slicer settings.

[rsd1982]

PLA prints better with raft for bed adhesion. I find skirt and brim useless