This game's not that hard to speed run actually. Most enemies can be easily dodged around, with the exception of Hunters (but then again, Hunters have been a bitch ever since the original game, so that's not surprising). Tinys (Thing in Trench Coat) is pathetically easy in this game as well. 2 clips from the handgun if he's a required fight, or just get near and back up quick, then run by after he swings.

You'll notice I went out of my way for a few pieces of ammo. While I was doing this particular run, I wasn't exactly sure how much I was going to need for the Final Boss(es) so I just grabbed whatever was mildly convenient. I fired every shot I had for the Grenade Launcher / Magnum and had only 3 Shotgun Shells left after I killed the boss, so I guess my estimate was pretty good. ;)

The only real troublesome areas were any place with Hunters. They suck to try and avoid, take a lot of shots to bring down, and move quick and hit like a Mack Truck. I despise them. Everything else went pretty smoothly.