I like your honesty and candor.
You'll be fine. Seriously.
I have nothing new to add, but i'll "talk" anyway.
Probably 90+% of anesthesiologist don't do SC lines, and never ever will again. don't sweat that.
Academic places put in A-lines way more than private practice jobs. I bet there are a ton of anesthesiologists that haven't done an a-line YEARS. They just aren't used that much in private practice because surgeons are fast, and they don't loose blood. As a resident, rotating at other hospitals including Kaiser, I was always shocked at the cases they would do without lines. My staff would always say (with reference to central access and A-line on what I thought where BIG cases like whipples and stuff) "put it in if you want, we usually don't for that."
But having said that, I have never regretted having an A-line. This year, have a very LOW threshold to put in an A-lines. Tell your staff you will do it after the drapes come up as to not delay anything. I can't imagine your staff having heart burn about that because it doesn't slow the room down, and it is pretty darn safe. Of the things you mentioned, A-lines are important to get comfortable with. Doing an ALIF? Put in an A-line. Doing a cercival fusion with myelopathy? do an aline? Belly case >4 hours? A-line. Someone fat >3 hours? Easily justifiable to do an A-line because a BP cuff every 3 minutes can cause nerve damage, make horrible looking marks and bruises, cause post-op pain, etc - have a low threshold for A-line. You can find them if you push for them.
Practice with ultrasound. If you get good at putting in an A-line with ultrasound with an in-plane technique, you are unknowingly improving your regional skills, AND your central - line skills. I never do central lines, but I don't fear them because I feel very confident that I can - with direct visualization - put a tip of any needle in any point in the body with great control.
Central lines...eh. I can't think of a real reason you need one ever. Seriously...why is a central line ever really needed? 14 gauge flows faster. With CardioQ or flowtrac, you get good enough data and makes a CVP useless. All of us have given vasoactive stuff peripherally - maybe it is risky, but so is putting in a central line. Practice putting in a RIC or two - that should get your seldinger technique down. (next case that turns 180, put a RIC in the saphenous - good practice.....and bloody as all get out.)