More things as I remember them. Here’re the basics.

Low-Magic World

Allowed Classes

Feats

Variant Rules

For Love Or Money

Homebrew’d Stuff

Low-Magic World

It’s the real world. There aren’t cure-flinging clerics on every corner. Magical gear is nigh unheard of.

Allowed Classes

After your first contractor level, you are free to do whatever with subsequent class levels. The following classes are all fair game. Generally, you can also use any archetype for this class if it’s A) listed on http://www.d20pfsrd.com/, B) not tied to the Paizo/Golarion campaign setting, and C) approved by me. Which is to say, feel free to archetype! But check with me first.

        Bombs, mutagens, and extracts are reflavored to be mundane.

        This is the only spellcasting class besides contractor that you can take levels in. It’s okay—Nightwish inspired you.

Instead of a mount, you can ride and charge on motorcycles.

        Duh.

Firearms are common, so the gunslinger receives gun training at 1st level instead of the gun smith ability.

If you take levels of monk, you must pick the martial artist archetype.

        If you take levels of ranger, you must pick either the trapper archetype or the skirmisher archetype. Yeah, they suck, sorry. No ranger spells for you. Also, no animal companions. You cannot choose any archetype that forces you to take an animal companion as your bond.

        Ninja is okay, too, I guess. Weeaboo.

Feats

Any feat from http://www.d20pfsrd.com/ is fair game, so long as it was published by Paizo. This includes the almost-always-banned Leadership feat. Check with me before any feat selection about which you have questions or suspicions, though. Also, I’m changing a number of feats, as follows:

        http://www.d20modernpf.com/characters/feats

        These are tentatively up for grabs. Not all are balanced. Check with me prior to selecting them. Also, some refer to skill rules, etc., that aren’t officially in use yet. Talk to me if you want to adapt some modern skills (like knowledge[tech]). :)

Variant Rules

                (USING THESE!!)

For Love Or Money

1 gp = 60 dollars = 6,000 yen.

When you want to buy something, just tell me what it costs based on your research on the internet, lose that much money, and add the item to your possessions.

Homebrew’d Stuff

New 2-Point Evolution: Construct Appearance (Ex)

An eidolon appears as a construct, and mimics some of a construct's abilities and weaknesses. The eidolon cannot heal damage on its own, requiring either curative magic or spells that repair objects to heal HP. Spells and effects that target constructs or have specific effects against constructs affect the eidolon as if it were a construct. The eidolon gains a +2 bonus on saves against disease, death effects, necromancy effects, paralysis, poison, sleep effects, and stunning.

At 7th level, this bonus on saves can be increased to +4 by spending 2 additional evolution points. At 12th level, this protection can be increased to immunity against these attacks by spending 2 additional evolution points (the summoner must pay for the 7th-level upgrade before paying for this 12th-level upgrade).

Although the eidolon appears mechanical, it is still an outsider.