I actually love packing. I do carry-on sized backpack, even if I check it in sometimes, which means I'd need to pack light, but I have a generic packing list that I adapt all the time to suit the climate and duration of the trip (pack the same for 3 weeks as you would for 4 days - 3 full outfits). It took a long time to set up the list and categorise it, but once it's done I don't have to do much except get a piece of paper and write down a new list for different destinations. It's so thrilling to pack! My backpack is the front-loading type (like a typical roller luggage without the wheels), not the old-school top-loader backpacks which are a nuisance, so I can carry it on my bag around the world.
I really dislike it when I get to a city where the tube or underground has tons of steps and everyone is walking really quickly around me and I'm just moving with the flow when suddenly, the person in front of me stops ABRUPTLY when approaching steps to press the handle of his luggage down to bring it up and then stopping again at the top or bottom of stairs to pull said handle up again. I mean, seriously. Step to one side and do that stuff; I'm being glared at by local commuters for stopping behind you! Sometimes I even almost clash into such people, which makes me annoyed for so many reasons.
But my biggest dislike has to be simply being on the plane. I am slightly claustrophobic and an incredibly nervous flyer (even though I'm getting better; actually managed to sleep on my last trip as the plane was taxi-ing to the runway!) and I just want to get off it quickly at my destination but noooo - it will always take forever to unload us people. Plus I don't really want to rush out with the other crazed people, so we'll always linger behind (which makes feelings of claustrophobia arise).
I took trains between cities when I was in Europe last year, and they were such pleasant experiences! Except for Eurostar between London and Paris because the check-in is similar to that at an airport, which makes me want to tear my hair out. In Paris, when we were taking the overnight sleeper train to Florence, we simply hopped on the train a minute before it took off and the conductor kept our passports and that was it! The only stress came from the slow-moving queue from which we collected tickets.
Another peeve is when solo travellers who always seem to want to talk to me. Especially one flight where the guy was basically chatting me up and I had nowhere to go (he was in the aisle seat); so I keep faking sleep even though all I want to do is finish up a movie. Was too polite to not chat with him.
I always get annoyed when lost in a city, but looking back, I quite enjoy the experience. I'm nearly a perfect type A when it comes to planning for travels, and getting lost is just part of the ability to let go of that control freakishness.