[Name suggestion]
I don't believe that it makes sense to think about tech points as a physical resource. Instead, call it bandwidth, and express it as a percentage.
I think this actually kind of makes sense: each chamber uses up a certain percentage of the reactor's bandwidth. The reason I like this name is because instead of just seeming like an arbitrary imposed limit, you could actually imagine that in "real life" a reactor would have a limited amount of bandwidth with which to control chambers. Plus, I think it sounds "techy" enough without being too cryptic.
Now, I realize that the idea of waiting for chambers to fill up with "bandwidth" doesn't work at all, because bandwidth is not a physical resource. However, it was kind of arbitrary to give tech points the job of being built up in chambers before they can be used. Therefore, just give chambers a startup time or warm-up period. This also removes the need for tech points being unrealistically "dumped back" into the reactor all at once when a chamber is disconnected, because bandwidth is not a physical resource. Instead, when one is disconnected, it just frees up bandwidth for the reactor to use elsewhere.
So basically, once you connect chambers to the reactor, they take a certain amount of time to start up, and then the reactor uses a certain amount of its bandwidth to continue to control them and receive their effects. The reactor only has so much bandwidth to allocate.
TL;DR: Bandwidth and startup time
[Separate, but complementary idea]
About that last point: "The reactor only has so much bandwidth to allocate." With the current systems overhaul proposal, if you run out of tech points, you can't use any more chambers. However, it would be much less limiting if we could add as many chambers as we want, but with smaller and smaller efficiency. This works with the idea of "bandwidth" because it makes sense that once you go past using up 100% of the reactor's bandwidth, the reactor has to reduce the amount of bandwidth available to each chamber in order to keep up with its load. Thus, there would be more chambers, but they would be less efficient because they don't have as much bandwidth.
The reason why this would be so great is because it would allow for a much wider range of ships. In the current proposal, you get to specialize in a few systems of your choice, but that's it. With this implemented, you would see more variety in ship systems; they would range from ones that are decent at most everything to highly specialized ships and everything in between.
This would also allow for some interesting customization of systems. You could manually allocate certain amounts of bandwidth to certain chambers to give them greater effect, whether through a control panel/menu, simply by building the chamber bigger, or by hooking them up with more conduits. Overall, this idea of diminishing returns with chambers would give players more flexibility than simply picking their six favorite chamber boosts, and flexibility is what StarMade is all about.
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