Like you, I’m relatively new to coach building in 2mm FS, having previously modelled in 4mm FS over 25 years ago.
The best kits I’ve built are the Masterclass BR mark 1 kits. They go together so well, probably because of the great designing and that they’re built from nickel silver. I’ve built 1 kit from Worsley works, which wasn’t quite so well engineered and was etched from brass which seems flimsier and not so easy to work with. I’m sure you get more detail than you did with 4mm fs when I last modelled. My biggest tip is to use a powerful 60 watt iron with a fine 1mm tip, got mine cheaply from Amazon, you can get clean joints quickly.