On the note of the railgun looking too boxy or low tech, here are 2 shots from the show of the Railguns brought to atlantis in Season 1 and of the Deadalus from Season 5. Not the first raigun is boxy, and the other is round, like the railguns we have now.
first, those railguns on atlantis were actually meant to be mounted on a 304, obviously they were modified to act as a mounted, man-operated AA emplacement.
second, the Daedalus railguns are obviously encased to protect against all sorts of things (weapons fire, radiation, deep space environmental conditions, etc). and dont need to have 1. the seat for the operator to sit on and 2. the crew shield against incoming fire.
honestly, those railguns are about as big as maybe an SUV right? whereas the ones on your turret model as as big as a 747 or so... the increased size means different structural integrity requirements, meaning the big 'planetary defence' versions are going to look different to the ones on ships. anyway, i wont go into it more because its not my place, im just saying sometimes precedent is valid, and other times you have to throw it out the window because its not applicable.
The Solar Panels are a backup to the Naquedah generators, which COULD fail and then what? have a dead weapons platform? Honestly, it is just an asthetic feature.
agreed about it being aesthetic, but from a scientific point of view, a Solar Panel array is much more likely to fail than a Naq generator (i.e. it being shot at), and Naq Generators would have backups... like rechargable batteries or secondary (Naq) generators. Not to mention they generate much more power than a solar array would anyway...
BUT! im getting off topic and being needlessly argumentative. for that i apologise. just pointing it out.
to be constructive, if i were designing it and REALLY wanted solar panels, i would put the railguns right next to each other, in the middle/center of the structure, and make the 'fuselage' long-ish and cyllindrical, in accordance with modern satellite aesthetics. i would then have 4 solar panels pointing outwards at the 1:30, 4:30, 7:30 and 10:30 positions respectively (the 1:30 etc refers to the location of the hour hand on a clock at that particular time)
depending on the dimensions, i can imagine that being more or less appealing to the eye. certainly more appealing than now though...
anyway, i re-iterate, great work, i cant wait to see the final thing. keep up the good work guys