Ive recently completed two projects based around a similar theme. Both tracks revolved around very simple Harp lines, Pianos, Strings and Acoustic Guitars.
I tried to create large soundscapes by sitting these key elements alongside reverb effects, synth parts and simple percussion, giving a feel of depth and space (i hope) to the finished pieces.
I´m current working on another project which is very bass heavy and electronic, so its been a nice distraction to get away from that and into this mellow world of Harps and acoustic instruments, but i guess now they are both finished its back to distorted 808´s and sidechaining.