Noisms at Monsters and Manuals things we need to talk more about some stuff.
Book binding. (I can't be the only person who bemoans the way new rulebooks tend to fall apart like a sheaf of dry leaves after about 5 seconds of use). I've all but given up on buying game bookss that aren't stapled in the middle. That limits me to smaller books but I'm okay with that.
"Doing a voice". How many people "do voices"? Should they? How do you get better at "doing a voice" if that's your thing? I do voices. I'm pretty sure they're terrible and have no idea how to improve other than listening to Billy West, John DiMagio, etc. discuss the craft on the commentary tracks for Futurama. They often discuss starting with a known voice and layering in the emotional tone of one or more additional voices to reach an amalgam. So don't shoot for just Merlin from Excalibur, try mixing it with the exasperation of Bones from Star Trek to achieve a new character.
Breaks. How often do you have breaks within sessions? I run short sessions, usually no more than three hours. One five or ten minute break seems sufficient.
Description. Exactly how florid are your descriptions? I try to keep it minimalist. My feeling is that if you suggest rather than explain the player's imagination will do a better job than I will.
Where do you strike the balance between "doing what your character would do" and "acting like a dickhead"? Most the PCs in my games are dickheads in various ways. I only care when the players are being dicks to each other. My personal rule of thumb is that the DM gets to be the biggest dickhead at the table. Anyone being more dickerly than me is asked to tone it down or leave.
PC-on-PC violence. Do your players tend to avoid it, or do you ban it? Or does anything go? I don't ban it, my games actively discourage though. If the world is dangerous enough smart players will figure out that the other PCs are their only allies.
How do you explain what a role playing game is to a stranger who is also a non-player? (Real life example: my friends and I were playing in the local M:tG club space. A M:tG groupie teenage goth girl came over and asked, "What are you playing?" "[We answered.]" "Sounds kind of gay.") Do people really need to explain what D&D is any more? I guess I once explained to an old lady it was like doing an action adventure series on the radio, but with dice instead of a script.
Alchohol at the table? Never really played with booze on the table. I run at a gamestore and I'm sure it wouldn't be legal.
What's acceptable to do to a PC whose player is absent from the session? Is whatever happens their fault for not being there, or are there some limits? I don't take attendance. If you don't show up the game goes on without you. No big whoop.