I see what you mean. But there are a lot of customers like me who have just purchased the case and are finding the available GPU options that fit this case are slim to none due to the state of the market. So in my situation, I'm really not interested in purchasing another case that's been widened to fit thicker cards, I consider myself lucky at having even gotten this one which was not even my first color choice. The reality is that if a current 2 slot GPU becomes available with a cooler form factor that's greater than 2.0, I'm buying it even if the cover won't close and hope that eventually:I'm not entirely sure about these spacers, I mean a slight increase might do us good as some new gpu's are just a little more than 2 slots. But a line should be drawn at 2.5 cards, because anything further would only provide us access to gpu's that are never meant to be in a case like this. And they would increase the size considerably to match the Ghost S1 or FormD T1 - which might be better options at that size, them allowing the use of 120mm case fans too (due to wider frames not just panels).
The main selling point of the Dan A4 compared to them is that it is thinner and smaller. This is the option it currently provides for anyone who are fine with 6 core cpu's and 2 slot graphics cards (like some 3070 or 3060ti) - which is realistically about 90% of people. With only increasing the side panels, we just make an inferior S1 or T1 from the A4 that is an overall better case for a humbler config due to it handling them well while being even smaller than them.
What I would not mind though, is increasing the FRAME on the gpu side just by a slight 3mm only, so that those new gen graphics cards that are a little more than 2 slots due to their shroud designs would fit. 3mm only might just be a worthy sacrifice - small enough, but would net the most amount of compatibility for that price. And the increase in frame would look better than a side panel that looks a little off compared to the other. And it would also further expand the usecase for 120mm aio's too (which we might see more of due to the upcoming itx gpu's that are in sight).
1. Dan offers a spacer to allow the use of the stock panel
2. Dan offers a replacement panel to allow taller 2 slot cards
3. Use the panel template to create a custom acrylic panel with a cutout for whatever GPU I end up with.