Sorry for dusting out this thread, but got some thought about it. Maybe I will code such thing for IC2, don't know...
But.
Advanced HUD sounds nice, but in reality there are mods that do most of that stuff. I rather would see a 3 tiered fetures (nano, quantum, graviton(something to that armor [Addon v1.97] Gravitation Suite v1.2 ! [SSP/SMP])).
Night vision, cause pontions are passe.... For nano, quantum, and gratitation helmets. Consume 1 EU per sek.
Waypoints - this is more tricky. There should be a craftable item (like redstone torch) that we put, named it (like sign), and on quantum, and gravitation helmets would show on. No power consumption. Still, this is supreme nice since I have natural ability to get lost even in my own base...
Map is something nice, but a minecraft maner map. So it would only show terrain where we went. Not a radar like thing. Also for nano, quantum, and gravitation helmets.
I like to see a ore detector (actually I would see something like x-ray, but for a range of 4-5 blocks, ores would be just highlighted not shown via textures). 1000 UE/sek or more.
Something another nice I would be an enemy detector. In vision would outline enemies on red, and when enemy is not on our screen then would just show something ike we see in battlefield when they shoot in us. This would also cost some EU.
Extended wather breathing would be also nice for quantum, and graviton helmets.
Main problem with quantum suit is that people don't really need it. It is just a way to utilize all that UUM comming from mass fabricators. I personally play with lappack, metoer boots (from thaumcraft), and apiarists helmet, and leggins from forestry (cause bees are awesome). I discover gravitation suite yeasterday, and think that that idea is awesome. And a good opportunity to make some room in chests, cause it costs a lot. (I think that I done second time quantum armor). Nano suit I used when IC2 was really new to me (and had only RP2, and BC installed at that time), cause I didn't know what to do with all that coal. But I wasn't impressed by nano suite, since it don't do a lot. Quantum armor was more for me. Leggins especially, cause it give that wonderfull speed. But helmet, boots, armor was pretty the same as nano.
I think that if quantum suite would give more content with it it would be more appriciated. But not OP content, like most of EE items does. I think that some features would be really nice. for example. If you have full suite on, then when in lava it could protect from lava for a short duration depending on energy left in whole suite. (max 10 sek on full batteries), the same with nano, but for much lesser time (for 4 sek max).
I would like to see quantum/gravitation suite give similiar abillities as nano suite from Crysis (especially from second cause it could be customized). That is another idea. Quantum/Gravitation suite could have a GUI to place upgrades similiar to thouse from MFFS. better jumps, seed, bonus to dmg, invisibility (freaking awesome on SMP), players tracking (that would be rather impossible in MC (without massive codding), as entities don't leave a trace, they are only are vetored in position), visions from AvP (similiar, newest batmat), and so on. To be honest it's all about making proper cost of features, and having ideas for more of them.
Now is why I wrote this post. I wanted to write a little mod that would give on HUD info about how much energy I have in tools (wih lappack), and armor how much energy it has, arrows left in inventory and so on. Little things. And I checked on this forum to see if there is such mod, cause I was watching this forum for a time now. And there is such mod, and for me is just not enought, and suggestion to make items do such things is greate.
PS. EU, MJ, Vis, and RP2 reader integrated in helmets is just awesome. Similiar to ThaumCraft googles of revealing. Have to see if IC2, and BC API provide such info/feature.