As it stands right now only AD based champions get to have good HP and mana recovery, via lifesteal and 
. Tanks can't have good HP recovery from items until they get 3,000 HP, but they don't get mana regen either. And then mages get no HP or mana recovery. Even 
doesn't do much. One of the most satisfying things in Dota 2 was becoming self sufficient to the point of not needing to go back to the fountain, even for items due to the courier.
Makior721 votesThere are plenty of champions including tanks that sustain hp and / or mana just fine.
Garen Renekton Nasus Chogath Mundo (ult)
All have either hp regen in some way or mana regen or both in their kits naturally. Even before items.
Fiora Trundle Irelia Olaf Illoai
Are some more examples of champs that can regen or life steal hp back either in their kit or with a botrk or something.
Maybe i missed the point of your thread but hp regen / life steal are fine. And for mana dependant champs tear is am excellent solution to their mana problems.
Mr Vulcanator1 votesI'm talking about items. I can't buy a Garen for HP recovery when I'm playing Vel'Koz.
Makior721 votes[{quoted}](name=Mr Vulcanator,realm=NA,application-id=3ErqAdtq,discussion-id=FgiI5VEa,comment-id=00000000,timestamp=2016-02-09T03:23:51.395+0000)
I'm talking about items. I can't buy a Garen for HP recovery when I'm playing Vel'Koz.
In the case of velkoz he shouldn't naturally have alot of hp regen. You do however have the option to build spellvamp on him.
Mr Vulcanator1 votesSpellvamp is reduced is reduced drastically if the ability is not single target. Vel'Koz has no single target abilities.
Calabok1 votesjust rip off some tentacles off of that squid lady and attach it to your torso. You are now Vel'Koz
Makior721 votesBut my point remains that velkoz shouldnt have much in the way of hp regen. He is a very strong mage and it would unbalance him alot if he could escape a team fight and then a few seconds later he has near full hp again.