Yamaha DX7, Lynndrum, Moog Model D, Roland SH-01, Roland Juno 106, Korg MS-20 should be all you need for the synth pop side of things. Just build some sequences in a MIDI sequencer or on a computer. Trigger the synths, modulate some cutoffs, record the output. Sometimes a hi-watt guitar with tempo matched delays are used. As for that sophisti pop I had to look that up. Deacon Blue has that song Real Gone Kid which seemed to be comprised of almost all acoustic instruments. In the music video the keyboard player was playing on a Rhodes MkV but I heard a piano layered with a string patch. Guitar for this specific sub genre seems to take a lot of influence from jazz guitar. And you will need a saxaphone. This genre reminds me of the bands Work Drugs and Pure Bathing Culture.