I like to lean towards health packs. We can balance the game all day in and out towards regenerating health, but the bottom line is that you can make all your near-death issues go away by hiding behind a chest high wall for a few seconds. This is usually the most common concept of regenerating health.
Not that the concept of having a finite amount of health is perfect. It requires more fine tuning which unfortunately some games aren't capable of accomplishing.
Far Cry 2's system is one I liked a lot. It took some of the only good things about regenerating health and combined it with the maintenance of healing kits. And it was entertaining as well (Some of those healing animations were
painful to watch.)
Although it worked out well in Far Cry's favor. Since it was a game about open world exploration, and a big thing about the game was preparing before making an assault, and health kit refills were pretty frequent. Something like this could be stretched to lots of other games as well.
Mr.K. said:
Regenerating health is lazy design and also fits well with the lazy gamer, you reset all your fuck ups every time you step out of the hailstorm of bullets, essentially negating all possible sense of consequence.
"realism" they call it...
Health bars/health packs are an added tactical mechanic that force you to actually avoid getting hit because the fuck-ups will stay with you.
I never even notice how important they are to gameplay until these modern shooters came along, then I went from a session of run&gun CoD back to Half-Life and got my ass handed to me.
The real downside is they require good level design and balance, something most developers prefer to avoid in the prospects of a quick release.
That's pretty much the way I look at it. A good example of a very strict concept of "fucking up" was SWAT 4. Besides the fact that one bullet could instantly kill you, getting shot at all meant having to deal with non-healable injuries that cripple your performance. Injured legs meant moving at a snails pace, injured arms meant horrible aim, etc.
It can be frustrating to deal with, but in general you have no one to blame but yourself for getting injured.
Back to how Far Cry 2 worked, the minor regenerating health basically allowed you to shrug off minor glancing damage, which could potentially add up to a headache in the middle of a fight. But became significantly punishing if you took too much damage too quickly(<-Usually constitutes as 'fucking up'). Needing you to use up your healing items. Which is the strong point of being able to carry your healing items instead of the old ways of stepping on top of health kits splayed out throughout levels. You can use one whenever you want to get your ass moving.
I can live with regenerating health, but the most common applications of it feels like a lazy handholding mechanic to me. I appreciate it when it can be spiced up in a way. Like in Far Cry 2, or even in Halo Reach, which regenerated only a small percentage of health.
It just feels appropriate, having lingering injuries that requires a health kit, given the fact that I was just caught in an explosion that wiped out all my friends. Regenerating to 100% health just by hiding even though I was horrendously injured by a rocket blast feels silly.