For glass blocks, notice a few things. Even out of build mode or holding other things beside blocks or similar there is lines for each block.Would be nice if the lines can disappear to make a glass wall, stairs, ceiling, or roof...or anything else like glass block well. For end result looks like 1 giant piece of glass and not each block.
I notice that if you glass block by stained glass block, looking through the glass shows up like clear glass block. Also the stained glass block looks like it does not let light through it.
For glass panels, they will not stack on top or line up over a wall. Example I did round blocks like log cabin but have gap between round blocks sideways. I try to use glass panels to seal the gap but only to put together touching the ground. Also to give the round blocks shiny affect. Only works if has a base and not floating.
To be honest i don't understand much of your point
However if you want gaps between blocks you can
1. Just leave a tiny space between them when placing. Since last patch you can drag - drop with gaps in between by using +/- key before placing the row
Or
2. Just place the glass and then take a thin block and mark the lines yourself and by that give the impression of separate glass blocks