Given that you have had extensive critical listening to both the SS-CS5 and DBR62 I was wondering how you would characterize their fundamental sonic differences? It is a given that the Elac will have better LF extension and from all I have read I would expect a less forward sound in the upper bands. But I have not seen any useful direct comparisons. Not looking for a pronouncement of one being better than the other, that is subjective in so many ways as to not serve a real purpose, but rather how do they differ in achieving their design goals for music presentation?
I also believe the Sony SS-CS5 is a great speaker. It was designed in response to A. Jones Pioneer BS-22 and I think it succeeded in that goal (not sure how sales have been - they did not have all of the hoopla that AJ/Pio did).
I have no trouble making a pronouncement of the DBR-62 outperforming the CS5 because the difference is significant in several areas - Detail, balance across frequencies, dynamics, etc. There may be somebody who prefers the Sony, but it would not be due to their wanting accurate sound!
I don't mean to beat up on the Sony's, but the difference between them and a well designed (i.e. - not one of the crappy) $600/pr speakers is substantial!
With your criteria of front ported speakers, the DBR-62 is a good candidate and I think you will be very happy with it!
In case you find a rear ported speaker that you love - Since you have a sub in the system,and as long as you cross at 80Hz, I would not worry about the rear port. I would plug it. These ports will be tuned to 50Hz or less (more typically below 40Hz).
Of the speakers on your list, I have only heard the Totem DreamCatcher. I thought it sounded lovely on something like a simple jazz trio or string quartet; however, they fell apart when I listened to music that gets busy with many voices (it was Frank Zappa in my specific case). I have no idea if this is a valid explanation, but I reasoned that Totem's declared intent to use cabinet resonance as a component of the sound results in a non-linear effect that gets over-activated when things get busy!
I think the idea of making the home office a better space makes all of the sense in the world since we are all spending so much time at home!