Currently using DirectX path and so yes on just Windows PCs.
2 RenderTarget2D used with what seem pretty default settings and a simple shader that blends between the two in the actual drawing target (there's an additional two targets used for blurring in certain circumstances but on starting the game these wouldn't be drawn to so hopefully they don't matter):
var pp = GraphicsDevice.PresentationParameters;
lightsTarget = new RenderTarget2D(
GraphicsDevice, pp.BackBufferWidth, pp.BackBufferHeight);
mainTarget = new RenderTarget2D(
GraphicsDevice, pp.BackBufferWidth, pp.BackBufferHeight);
The resolution of the game is 960x540, I do immediately switch to fullscreen (with HardwareModeSwitch disabled due to having a prior crash with that on).
Largest texture is 2048x2048 though for ingame it's 1159x924 (I don't entirely know how it ended up at that size!). We did previously have a texture 5000x11000 which did cause issues on some PCs but have since removed it!
In terms of crashes I have got a try around the whole program but this doesn't seem to catch anything in this case as the game still runs, just doesn't display anything but white! I'm not sure if you know of some flag for monogame that would cause it to throw exceptions in unexpected circumstances? Or perhaps I need to query graphics card capabilities?