One thing I'd consider, is balancing the options.
I assume that money and treasure distribution, as well as what happens to dead PCs to be an in-game party decision. As a GM, I might advise them to play nice, but I can't forbid them from doing things that are plausible in game.
1) In game, the players can solve a dead PC by spending 5K GP and the PC losing a level.* I would assume this solution doesn't get the player back in the game right away, as the party would need an in-game opportunity to be able to do so (like walking back to town with the body).
2) If the dead PC had a henchmen, they could actively take him over (certainly a practical "keep playing" solution. This HPC is presumably 2 levels behind the PC per the henchman rules. It may also be assumed this henchman will wander away if the PC doesn't make him a full PC (as he his buddy is dead and nobody else paid for the Leadership feat to have him).
3) Or the GM has the player bring in a new PC (whether pre-gen or not, that's secondary). This is where the "Death Tax" topic really comes into play. It can certainly be defined that a PC with a Henchman paid for that opportunity with a Feat.
I think it would be fair to say that the "new PC" solution should not be worse or better than the first 2 options. if it was better, than players who choose to drive their henchman got screwed. If it was worse (especially worse than #1), than the player gets screwed by the rest of the party because they refused to get him raised. This could actually be considered a PvP attack. Sure, they didn't kill him, but they took advantage that he was down to loot his body and keep his stuff so his new PC comes in worse than if they'd raised him.
*I wonder what level the OP was that the party couldn't pony up 5K, yet still invested so much into their PCs that losing one sucked.
Since part of the problem revolves around equipment and "wealth by leve" would it be fair to declare some expected rules of in-character behavior towards gear?
If the new PC is the same kind of character as the old, the party has to give the new guy the dead guy's gear. perhaps roleplayed, "hey, we just lost a man, join us. By the way, you look like you need some equipment, we lost a man, and his stuff will probably fit you"
If the new PC is completely different, the gear must be returned to his family, buried with him, or donated to his church. Perhaps role played as the societal norm. As far as looting, only bad guys loot (monsters I kill). As a player, I've never opened a tomb and found a +2 sword I could use. I always got my stuff by killing monsters or BBEGs.