After playing some days of Minecraft again, it somehow made zap and I understood how his redstone magic works. I created some NOT and OR circuits and combined both to an AND gate. So this made me wonder: can I now also create a decrementer like I did with C's preprocessor? I proved to be a bit more difficult to "invent" such mechanic, but after listing and analysing the alghorithm of bitwise-addition by hand, I noticed that I'd need an XOR gate but didn't knew how to archieve. So I took a look at Wikipedia, created my first rather large design and noticed how incredible big and thus useless for more complicated things it was.
So you get it, I figured out the right architecture but couldn't find it worth testing out. I mean seariously, how in does want to make something more complicated other than basic logic that can't be reduced to a surmountable size? However, the fan-driven Minecraft wiki brought some more compact XOR designs to me and I saw how differently you can interpret and create an XOR gate. It's quite varied in size, function and output position. In essence I was able to create some basic decrementer, but for some reason(s) some numbers didn't drecrement right and I decided to give it up making even bigger circuits. Designing is easy, testing requires simulation, creating it in the game or simple by checking whether is works on paper. But geez, that's just to cumbersome for me. It's one thing to work with Lego bricks, but another to combine them atom by atom.
So yeah, unless it get's some more useful updates, I don't see any reason to add more things other than simple logic or preasure plate-triggered lighting effects. I bet that's the reason why they implemented it, not to enable one to make an own computer in his game on a computer. Still said that there isn't any way official to convert redstone to kinetic energy except using preasure plates and dispensers or doors (though the last one doesn't work for anything else). But atleast I got an idea how to get remote minecart release to work. But that's no tested and would probably not work as well as just running.
*sigh* So back to ceiling lights... I wonder whether MC will ever get some simple logic elements with wasting huge amounts of space and redstone. The redstone repeater is only one step and I can remember seeing a mod with logic blocks and so on. Would like to pick one this time. However, today I realised how simple to grasp those computer systems could be. But the execution is error-prone and hard to realised with no ability to copy components on demand. So that's the good thing about reallife circuitry: buy some chips and it's done. No wire-by-wire placement, no atomic build-up. Simply put it in and link. Think I got closer to understanding computers and circuitry better. It's good that you can see how Minecrafts circuitry works, otherwise I wouldn't be able to grasp even a thing.