If the pain aversion wasn't enough for most folks to not consider it, suicide in many faiths is considered a pretty big nono.

Roughly the rules are interpreted as if you spend your life in the service of somebody else or society you go to heaven. Of course, those in power see themselves as serving society because they give guidance. If you do things going against that, so disobey the leaders, you go to hell. It's how they tried to keep the populace in line. The rest is window dressing.

Yes. At the same time some aren't that sure or scared of death. And the rules are that detailed that lots of people have committed some kind of offense and can't expect to go to heaven for sure.

Also the bible has implemented some additional rules so you can't take a shortcut to heaven... Suicide won't do it because (surprise) it's a sin... And generally speaking god is just testing you with this life. That's kinda the only thing why it matters and why you would want to behave and live it like he intended.

Also there is martyrs, suicide cults etc taking that shortcut straight to heaven.

No, they're scared shirtless of death. They know despite the self righteous facade that they are shitty human beings and expect to find themselves in hell.

you’d think so, wouldn’t you? it’s crossed my mind about a thousand times over the years.