The Macbook Pro is a good machine and there’s only one model you’d want. The 15″ with Intel Iris Pro Graphics + AMD Radeon R9 M370X with 2GB GDDR5 memory. It’s the only model with a dedicated graphics card and the only options are for processor (all quad i7) and storage (512gb or 1tb) so that’s an easy config.
Only the Retina 5K iMac gives you the i7 processor so that’s where you want to be there. The iMac configured about the same as the MBP is about $500 more.
Either one would be great for what you do. I worked off a MBP for years with a thunderbolt monitor at the office and on a iMac at home. About the same.