I like the idea a lot, but the concept is beginning to overflow into the realm of being "overly busy", in my humble opinion. The Tron aesthetic is one of purpose yet efficiency. They're essentially designed around electronic circuits (look at the concept art for the original Tron film). Tron Legacy "streamlined" that design aesthetic, adding a sort of "Mac" quality to everything, but the underlying aesthetic remained the same. Clean lines, flowing but efficient, artistic yet purposeful. Consider how a modern circuit board is laid out.
Might I suggest, now that you've build a "3D model", that you first start with a bare tube, then pick one or two primary "lines of movement". In other words, a line which begins at the front of the saber and ends at the rear. Pencil those one or two lines in, and then sketch detail around those primary lines of movement, without necessarily overcrowding or crossing over those lines. Tron artwork often features two parallel lines which then diverge in opposite directions (again with the Circuitry aesthetic). Try incorporating that into your design.
Sketching onto an actual tube helps you see how all the lines and angles balance together when viewed from all angles. You'll quickly be able to see when you have added too much detail, too many complex lines, too few "bold strokes". Concerning detail density, in my opinion there is a fine line between a Tron saber, a Michael Bay Transformers saber, a Borg saber, and a hot mess.
To summarize my suggestions, seek Balance.
P.S. Don't fret the cardboard tube, my friend. I've used laundry sticks in the past and your method is much cleaner. Whatever works! 8)