Okay, I've playing DoomRL for a while now (without bigger success, though- only one win) and, well, there is a few things that I would be really glad to see in game:
1. Invulnerability and berserk equals Badass - Okay, it seems strange for me that even if you are un-killable or nearly un-killable and immune to pain your health still drops if it is over 100%. What I suggest is that Berserk Globes and Inv. Globes grants you Badass (3) for the duration of their effect. It is not a big change, but a sensible one, I think.
2. Hell's Arena rewards- I suggest that beating Arena level 3 would give 50% chance that one of its rewards turns into unique weapon or armor. Just like in Hell's Armoury. Well, Arena rewards are rather small, compared to it's hardness, at least for me, and I usually skip it. But, if this would get implemented, entering the Arena and risking your life there would become much more interesting option.
3. Unique destroyed message- This is rather cosmetic- if an unique gets destroyed due to some unlucky accident, barrel for example, you would receive a message, something like "You feel that something valuable was lost". It save your time when you're searching for an unique which is long gone.
4. Second advanced pistol for AoM- Simple- second advanced pistol is guarantee to spawn on level 10 in AoM runs. It would make it easier for all those unlucky ones, who can't find an unique pistol on the whole run.
BTW: Sorry for my poor grammar, English is not my native tongue.