I have been buying more shirts recently but on the casual side have been struggling somewhat on finding shirts that fit well. For work/dress shirts I'm a big fan of the Charles Tyrwhitt extra slim shirts as these seem to fit pretty perfectly though are of course cut to be tucked in and fairly simple design wise generally.

I would like to pick up some more shirts that are cut to be worn out over jeans/trousers and more of a selection of patterns etc. Ted Baker, Paul Smith and Reiss all have shirts I like and have some of, but I'm finding that on the slim fit ones the arms are generally too slim or they're cut too straight on the sides so there's a lot of material at the bottom. I suspect the answer is that I'm going to get is to get them all tailored or MTM but any brands work well for the more athletic build with a fair difference between waist and chest size?