Before I was active DM, I thought computer initiative and rule aids would be great. As a DM, I don't imagine they would be for several reasons. A) I have accumulated an encyclopedic master of game rules (running the Pathfinder system, perhaps the most complex D&D variant). B) Dice and tables have a certain "feel" to them that stopping and doing something on one's laptop just doesn't. C) In person, I keep each players stats on a 3"x5" and stack the cards for initiative - this solve 99% of initiative problems, it has a nice physical feel and all my players, some of who will be computer-incompetent if not computer-illiterate.
I say all this because I think there are places where computer aids could shine:
1) Character generation - despite lots of projects, there's nothing yet that quickly and complete edittable characters for Pathfinder at least.
2) Map-aids for PbP. Roll20 and related systems simulate the whole in person game framework. Discord and most PbP basically just let you roll dice and maybe change stats with markup. A markup system that also allows change one's location on a map, along with system to manage that, would be cool and make the PbP system richer without forcing it into a "heavy" Roll20 type approach.