1) Update in real time: Pretty much the only way to update the minimap atm is to open the map. Until that moment you could be running off a hour old minimap, simply make it update every 5-10 seconds so it keeps up to date without immediately showing any minute changes the enemy couldve made and itll be perfect.
2) Pretty up the coords (.76): Atm its just this ugly, hard to read black number right above the minimap. What i propose would kinda fit the theme of the game is a slot machine esque letter/number system (wow that sounded pretty bad). Itd be kinda like the hp/pp system from earthbound, meant to be kinda like an army instrument or something.

It doesnt have to animate or anything, itd simply be a themed white box thatll contrast with the letters/numbers making it easier to read and more appealing than a simple white box or something.
3) Display how much time is left till the next spawn wave: Simple enough, useful if you want to switch weapons without waiting ~30 seconds and will also allow you to strategically kill the enemy to cause them to wait rather than immediately spawning. Could be displayed as a stop watch or something.
I know I know, not really well thought out and lacks all the pretty pictures you all want. But still, these are all fairly reasonable and I feel I'm not the only one whod want this.