Main Ideas:

• A circuit schematic gains different complexity values depending on the amount and types of gates used in it. Current plan is 3 different stats: basic complexity (io, logic-cates, comparators), advanced complexity (arithmetic and other advanced gates) and memory (= bytes used for all variables combined)
• Processors are build in an assembler block out of a base component that determines maximum io-port count and size. Other materials can then be added to build up the required complexity stats from above. However the amount of materials that can be added is limited by the base component's size value.
• Circuits consume power for each cycle they process which is taken from a small internal buffer. But the internal buffer will recharge on its own with a rate that depends on the materials used for assembling the processor. So if the circuit runs slow enough or the passive recharge rate is high enough it can run on its own, otherwise external power supply is needed.
• For assembly materials basically any item available in the modpack can be registered. The general balancing idea is: Big clunky components (like raw redstone, quartz, etc. ) that offer low complexity per size but cause high passive recharge versus small integrated components (microchips, electronic circuit boards, etc.) with high complexity at low size cost but basically no passive recharge. And maybe also some "booster materials" that only increase passive recharge at a small size cost (Uranium, Pellets of RTG-Fuel and stuff like that).
• For very simple circuits there will be a Prototype Processor that offers some basic complexity stats and can be directly crafted from crafting grid without needing to tinker with the assembler. And of course also a Creative Processor.