I really can't imagine how you can play Heroes at high resolutions where everything is so small.
Just a reminder, the optimal resolution for widescreen users is 1180x664 (even if the monitor is 1920x1080). The stretch filter is up to you. I personally use "Bilinear SharperX2". And the picture makes me very happy in full screen. Nothing is small. Everything is high quality, and the image is much better than the original 800x600.
So, it's all a matter of taste...