Awesome! Here's my take:
Dermatology - Steroids on rashes
Gen surg - obese patients and removing the organs they mess up along the way; suturing up adipose and sending the patient back to his bariatric bed. Have nurse find the closest Open MRI in the area.
IM: Spiriva/Nebs, Metformin/Lantus, Labetalol/Narcan, Lasix/Lasix, Aspirin/Plavix, Zofran/Maalox
Anesthesia - Insert tube, needle, rx patient and zap their forehead every 10 minutes while playing Angry Birds on your phone
Pulm/CC - RTs do really do all the work based on protocols written by some authority institution that they all follow to the letter or risk Medicare not paying them. Do maybe one super-complicated procedure (lung tap) every few weeks.
Emergency med - Have the Med Students see the patients, Residents staff the notes and check boxes on the standard orders for most ailments seen, truly no memory required
Ophtho - Assembly-line surgery where the Opth spends maybe 20 minutes in each room.
Ortho/hand - Furnish a house completely from IKEA and you'll have a bunch of those little hex screwdrivers and the same training.
Trauma surg - Dead/non-dead; Fix Now/Fix Later; Admit/Discharge home
OB/GYN - Memorably foul smells coming from that region with swabs of substances to match. Aides putting mom in lithotomy position if she spikes a BP of 122/82 and is confused about where her husband parked. You arrive, wade your hands through the urine, blood and feces spewing out and pray you don't see feet first.
Infectious disease - Some type of penicillin with some sort of quinolone with metronidazole for good measure. Return when cultures are back and adjust.
PM&R - Read police report, cast, bandage and write a PT/OT prescription. You, rarely, may have to write an Rx for a pain med.
Psych - Where can I call your Xanax and Zoloft in to? You'll have to carry this Adderall prescription in by hand.
The last 3 have very little overhead with regard to office space, equipment and staff, so your earnings per hour have the potential to be much higher, if you run your practice right. Everything in most fields will become basic to you after doing it for a while, that's what residency is for.
Spend some time learning how the RVU system works. Most doctors get their $30 an RVU multiplied out by something, no matter what specialty, if they take Medicare. Most will still be forced to take it to make things meet for a while. If you actually get paid at least $150/hour (yes, you'll bill for a lot more) for 8 hours per day, 5 days a week, that's between $200-250K per year at a minimum, no matter what your specialty. You keep a lot more of it if you have low overhead.
Under no circumstances should you even consider FM, for any reason. You did not spend $150K ($350K if you went to DO school) to drive the same car you drove in med school to take the family out to Applebee's once a month for the latest coupon meal where you sweat if your three kids are going to be OK with sharing a dessert again.
Dermatology - mostly just steroid creams, super easy
Gen surg - appys, choles, hernia repair. send the colons and spleens to a specialist
Anesthesia - sux, propofol, sevo, roc - pretty much it
Pulm/CC - respiratory therapists doing all the work, just write boilerplate orders
Emerg med - have the PAs see the patients, double check stuff on uptodate - no memory required
Ophtho - ODs for refractions, pump out lasiks all day
Ortho/hand - I mean its only one body part! same could be said for ortho doing all TKRs
Trauma surg - find hole, patch hole
OB/GYN - people have been having babies without doctors for millennia, just let nature work
Infectious disease - least memory required here. Vanco/zosyn wait for cx results
But yeah def steer clear of FM