Good morning.
@matigo Yeah, fiddling around with the hardware wouldn't be an option for me. I replaced the HDD of my old MacBook with an SSD a couple of years ago, and it didn't work out very well. I chose the iMac with 16 GB RAM and am pretty happy with it.
@matigo If I could go back I would do it differently too. Instead of ending up with two Macs I would have beefed up my rMBP with 16 or 32 GB of RAM and bought a 30" Display. Would have cost about the same as my 27" iMac, and the setup would make a lot more sense.