Underworld Systems and Character Types

Forgive me if this is a bit rambling.  My thoughts on these subjects are a bit half-formed, but I feel like I need to get something about them hammered down before I continue developing the Underworld.

In the days when the Underworld was called the Lost Lands, I went through a number of possible system options.  It was originally designed alongside a homebrew system created in order to fill the requirments of Matt Finch's Quick Primer on Old School Gaming while still being appealing to the new schoolers I played with.  It did this with some success, but it lacked the kinds of guidelines I like when making wilderness and dungeon areas (such as No. Appearing and Treasure Class).  I toyed with using the "Lost Lands" as the basis for a Swords & Wizardry based game, even going so far as to write up a pretty extensive house rules document that is now lost to the ages.  I've even considered using a combination of yellow book BRP and the Bronze Grimoire to power the setting, but nothing came of that either.

Now that I've picked it up again (as a side project) and given it a bit of a face lift, I need to think about what system I'm going to use to power it.  Obviously, I could go the route of Scott of Huge Ruined Pile and make all the material as systemless as possible.  I don't feel comfortable with that option.  The amount of  changes that would have to be made to any given system to accommodate just the monsters is pretty large.  Almost all of D&D's monster list is completely useless.  The only exceptions being certain undead and summoned monsters.  I'm fine making a wholly new monster list, but I wouldn't want to burden some other sap who decided this setting was the bomb and wanted to use it in his or her home game.  Therefore I need some system I can provide stats for, though I will probably put out little handouts on how to run this setting with other systems.

So what system?  I'm currently getting better acquainted with Labyrinth Lord since the group that I will be DMing for is relatively familiar with that system.  I'm also a fan of LotFP:WFRPG.  So some sort of B/X D&D hack?  Well... no.  I've never really been comfortable making monsters for those systems as I never know how much xp they should be worth.  The most likely answer is the Swords & Wizardry White Box, which is by far my favorite retroclone.  It has a bare bones sensibility that I think will lend itself well to tinkering and this project in general.

Of course I could pick up another side project that would fill a similar niche in my creative efforts but not be as arduous a task.  Possibly more on that later.

With that out of the way, I need to decide what character types I wish to represent with these rules.  Fighters and Magic Users fit in easily to the setting.  Clerics stick out like a sore thumb.  They fit great in Nightwick Abbey's pseudo-Medieval milieu, but their holy magic and mace wielding antics are a poor fit for a setting where even the nicest gods have terrible serpents for pets.  I could just stick to Fighting Men and Magic Users, possibly importing LotFP:WFRPG's encumbrance rules and lack of weapon/armor restrictions, but I'm not sure about that yet.  I feel like I want to allow some other class options for the players if only to give them more options.

That being said, none of the other classes developed for TSR D&D strike me as appropriate for this setting.  Thieves could work, but I find that they generally muck up OD&D.  Still they are an option.  The others work less well.  I'll probably have to create some of my own with the setting in mind, but I'll burn that bride when I cross it.

To close, here is an inspirational image for the setting:

Now back to thinking about Nightwick Abbey...