It sounds to me like an inflexible DM is the real problem for the OP. In earlier editions, like he said, the DM may have
wanted to force players to play the godawful stats they rolled. But guess what? It's a cooperative game. You try and force the other side to play things they don't want to, and problems arise. Not really surprised they chose suicide to get a new set of rolls. If that's the only escape route the DM's left open, it's entirely caused by him that anyone unhappy with their PC takes that option. (If instead he simply didn't allow PCs to commit suicide, I imagine they would have left the game entirely or bitterly stayed in, building a steady grudge towards the DM).
Then new options come out and players want to add it in or switch characters, and the DM says the only way you get a new PC is if your current one dies. Gee, could I ever guess what's going to happen after that?
In my games, I let PCs retrain their choices if they're unhappy with them, at least to a point. If they're trying to tweak things between every session, I lay down the law. Similarly, if a player decides he wants to play something else entirely, I'll just let the current PC leave the group for x reason, and have them part ways. If there's a tough fight and a PC was going to be leaving soon anyway, the player might opt for some sort of heroic death to help his comrades, whatever. In any case, once a PC leaves the player's hands, (alive or "raise dead ready," I don't care) he's
mine. An NPC. To use however I like to further the plot or possibly turn into an enemy of the party. Or he just goes off somewhere and plays no part in the campaign. Up to the DM.
Makes for happier players and more coherent plots.
Oh, just to address this: we had a firm policy of magical gear leaving WITH a departed / departing PC, and new PCs getting a level-appropriate chunk of loot.
Cheers, -- N
Every group I've ever been in has been the same.