Reddit reviews Adiyer 10 Pcs 8mm OD 20mm Length Compression Mould Die Springs for 3D Printer Ender 3 Stock Bed Leveling, Light Load

It's generally better to use it stock and upgrade as you discover the need to.

The only (purchased) upgrade you really need from the get go is [better bed springs] (https://www.amazon.com/gp/product/B07KF9LZ2L/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1). The stock ones are terrible at maintaining the bed at level. If the bed it comes with is warped, then also a glass bed, but that's the only reason you would need one. Mine wasn't warped and it's just fine. After that, aluminum extruder because the plastic one will start to wear eventually, and capricorn tubing.

A Pi, auto leveling, new electronics, micro swiss are all much more in the "luxury" upgrade category in my opinion. I don't have any of those and I don't feel any particular need to after three months of having the printer.

Make sure you also look into what's called "luke's hotend fix." I struggled with an underextrusion goblin for a while until I did that and upgraded to an aluminum extruder and capricorn tubing. Goblin banished.

I recommend also getting some calipers, though they're not necessary, and a set of feeler gauges has made bed leveling easier and more consistent than using a sheet of paper.

edit: I misread and thought you were trying to save money. Anyway, I still recommend using it mostly stock for a while to get familiar with it before upgrading a bunch of stuff. Out of those, after bed springs, extruder assembly and tubing I'd probably go for the electronics and hotend since bed leveling comes pretty easy to me now.

Upgrade your bed springs: https://smile.amazon.com/Adiyer-Compression-Springs-Printer-Leveling/dp/B07KF9LZ2L/

In my opinion, this is the MOST necessary modification to do on any Ender 3. The springs that come with it are trash, and your bed will constantly shift up or down unless you get better springs. I haven't had to re-level my bed using paper in months.

I'd stick with the glass bed if I were you, it really helps if your bed is warped (which it probably is, judging by your first pic). Just from looking, it seems like your nozzle is too close on that second pic. If you're using a piece of paper to level, make sure to check the nozzle height at locations all over the bed, not just on the edge or the center (although the center is probably the most important spot).

Also, just a reminder to clean your bed with alcohol often. The Creality glass bed can be VERY sticky if clean, so it's actually pretty forgiving on that first layer. Your nozzle can be slightly farther away than it should be, but it will still adhere fine. But if the bed is dirty you'll have a lot of trouble.

Replace the Bowden pneumatic clamps

https://www.amazon.com/dp/B073TTWWN1/ref=cm_sw_em_r_mt_awdo_uweXCbDCRQK7D

Capricorn Bowden tube

https://www.amazon.com/dp/B07B67GG75/ref=cm_sw_em_r_mt_awdo_VyeXCbA0WGRWQ

Springs

https://www.amazon.com/dp/B07KF9LZ2L/ref=cm_sw_em_r_mt_awdo_zBeXCbD24BJN2

Here's the aluminum extruder assembly. The plastic one that comes on the printer WILL break. It's just a matter of time. They crack from stress after a while and even before that they creep and you'll start getting missed extrusion.

Here's the stiffer bed springs. You won't have to compress these as much to get a good stiffness.

Another really popular upgrade is this glass build plate. It has a special coating that makes it so parts stick without adhesive, and it leaves a really smooth surface on your prints. Parts stick really well then when it cools down they self-release.

The 3 upgrades I linked are extremely popular upgrades. You can get by without the glass bed, it's just an option because the stock bed will wear out eventually.