I got some input regarding the new 64x resource pack and it seems the downsampling filter I used yielded too sharp results. I took the time to fiddle around trying different filters and came out with a solution which would retain enough details but without too much noise.
Here’s a comparison of the previous sharp filter vs. a filtered image. Those filters are not the ones I decided to use in the end but are already much better looking:


Here are some final screenshots from the 64x version y’all be receiving starting next version !
Those were taken with BSL shader :
Those were using PTGI E9 :
Don’t hesitate to tell me what you think in the comments or on the ShaderLabs discord !