What kind of pokemon needs or does very good if getting HP maxed out? Is it Pokemon who can handle "a few" hits like snorlax or armor pokemon like tyrannitar?

As for now i can't come up with someone that Needs HP-maxing out. The mostly i think of is needed, is either that normally type of attack (atk/sp.atk) and speed or both sp.atk and sp.def, but noone who basically needs more HP-ev training. .... okay everyone might need hp so they dont faint but it will still not be high priority, if it has good attacks it will knock out the foe before he can faint self

Lots of Pokemon need HP Evs
Any Trick Room Sweeper Pokemon generally have max HP and MAx SpA or Atk as they dont need the speed EVs. HP Ev'ing is mostly used for walls such as Cresselia, Lugia, Multi Scale Dragonite etc. Also many Pokemon have HP Evs as it covers both defences insted of doing half half for both defences. Most sweeprs also have the last 4 Evs in HP as that covers both defences. Also walls are very effective and take much more then a 'few hits'. Have you ever faced a Multi Scale Luigia? Thats so annoying when it roosts back to full HP...

okay. mostly i dont use trick room Pokemon. No i have not met a Multi scale Luigia.. but in a other way .... is it like a lvl 1 trying to tackle a lvl 100 kinda ?^^ I have faced a muk with black sludge in the pkmn league ^^ attacking that one with "it's not very effective" is a hell of a job.

I recently figured out i could give EV training a chance. Should i get a whole new team or just keep going on my now beeing team even they have gotten a little spread on the EVs ?

ummm - it depends on your choice really. anyway if you EV train youll notice the difference straight away, youll be a much better battler

make sure you also Ev reduce if your using your existing ones

EVs and natures mean a huge amount of difference. At level 100, a minimum special attack alakazam will be as low as Glalie's. Most defensive Pokemon, like Gliscor and Blissey, usually want HP EVs. A lot of them actually want maxed out HP, as that gives them bulk on both physical and special sides. Also, any priority sweepers, like Arceus and Azumarill, prefer max HP to max speed, because they already use priority.