The majority of the time you spend will be spent slaughtering mobs and elites. During a rift guardian you'll be burning it down fairly quickly with most specs, either popping a cooldown or otherwise (my igni-ball spec becomes gradually stronger the longer the fight is), and most damage from a single big mob is hilariously easy to dodge effortlessly.
As for elite packs, your spec seems to be a Wand of Woh spec? A link to your char would really give me more info, I can't even find anyone searching Bilets#2974 on EU/US diablo sites
. If so, that means that most of your mobs either need to be in close proximity to be taken out, or will be smashed instantly. Playing most wizard specs gives you the advantage of range, though, which means that you can aim your cleaving attacks (arcane orbs, magic missile ignite etc) to hit both elites and white mobs, and you'll be kiting elites to avoid damage in most cases (where you would stun them and blast them to shreds with teleport->EB), giving you ample chance to reposition to catch white things in your line of fire.
Edit: Found your char searching for zolia on top of the bnet. No WoW, but you play the same style as a WoW spec would due to your Moonward necklase.
It does, however, seem that you don't play solo often? Your followers aren't geared at all. In group play, you can get away with far less HP/survivability in general, mainly because 100 mobs having 2-3-4 targets is going to dilute the amount of hits you end up taking/soaking, very obviously. I question your ability to stay alive for the entirety of say, a T4 gaming session alone.
That said, you have almost zero sources of regen, so it's pretty clear that having more HP probably wouldn't help you survive better either way - You might survive a hit more, but it won't improve much, and it's basicly at the same level as mitigating more damage (AKA, no "long term" benefit). You've got the LoH from paragon (although I'd call that a waste, AOE damage is by far the best stat to fill in first) and 8K life per kill on your neck, Essentially, during a boss fight with no mobs around, you have your potion and that's it. No other sources of regen.
http://eu.battle.net/d3/en/profile/D.../hero/35820468 is my char for reference. I've got about 50K life per globe/potion bonus aswell as my 14K LoH, and play almost exclusively solo, so 5K regen + the heals from my templar and then 4K LoH from my 200->400 paragon points.