Derailleurs work well when properly set up, and almost any setup will give you a good gear range and spacing. However, I prefer an IGH due to the simplicity of operation- there's one shifter, and no hassle about cross-chaining and juggling two shifters. If you want a higher gear, you just shift up. In snow or freezing rain, ice can sometimes build up on the sprockets of a derailleur setup, preventing shifting.
I get around fine on a 3-speed Sturmey Archer hub, which have been around for decades and are virtually bombproof, and only need a drop of oil occasionally.

For a commuting bicycle with derailleurs, you will probably get by quite happily with a 6 or 7-speed rear and a single front chainring. This keeps the simplicity of operation as with an IGH. If you can't get enough range with a single chainring, you could have a 'granny' chainring as well. Most of your riding would be done on the larger chainring, with the 'granny' there for hill climbing in the larger rear sprockets.