I tend to do pretty simple things that are designed in 2d and use a 'tabbed box' style of assembly. ... its not glued, its floating and just screwed with standoffs and screws, so its open-able and fixable (the way I like it).
That sounds good. Binding posts on the short side?
maybe people can throw together some images (3d mockups) of what they have in mind and we can find something that works for most of us.
I often start with this site
http://boxdesigner.connectionlab.org/its pretty well known, by now, and its pretty simple. enter the dimensions (outer, I believe) and it creates a pdf for you; you import that into your 2d editor (I use corel draw since its what our lasers at tech-shop mostly use) and you add whatever panel cut-out shapes and lettering you want. edit some of the tab notches, if needed, do a dry run using cheap cardboard instead of plastic (I often will get something wrong and its nicer to waste cardboard instead of good material).
what I do beyond the standard box maker is to add a rim around the top and bottom plates and allow for pcb style standoffs to be used (long ones) to screw into top and bottom holes. if the rim is extended beyond the box dimensions, then you need to edit the 'zipper' tabs into rectangles that the laser will cut; those become locking tabs that keep the sides from falling out. this method is glue-less and depends on the standoffs being the interior height of the box and being screwed to the top and bottom. here's a photo of one of mine, maybe it will be obvious what I was trying to decribe
'top and bottom' are relative, if it makes sense to put the rails this way, whatever works for you. one optimization is to use those standoffs as ways to secure rubber feet to the real bottom of the box. rubber feet with holes and #6-32 screws work well and its easy to find 6-32 thread hex or round standoffs and either stack them in unison, all 4 corner posts; or get long ones to-size or cut them all to-size. if they are threaded on one end and tapped on the other, they will stack and you can screw the rubber feet into the female side of the standoffs. the top of that stack has exposed thread ends, and so I tend to use finished nice-looking acorn nuts and just hand tighten them. it holds the box together, it lets me get inside easily, there is no need to glue things this way and each panel is replaceable since its just a bunch of panels. if you get panels made, get extras made and when things get scratched or broken or old looking, refresh it with replacement panels
anyway, that's what I do for DIY panels. its cheap, it works well and while it has a bit of a strange look, its very practical in many ways and if its not meant to sit on a shelf and look pretty, its actually pretty enough for its job