In my original idea I had some more things to make "Circuitissimo" useful.
I'll describe some of them here, so you could, if you wish implement them.

Thought 1
When you have this complex combinator you would want more inputs and outputs in it.
And with this number of inputs you can easily misclick or forget which one is for what.

SUGGESTIONS
I suggest making say 4 inputs and 4 outputs.
But that would be hard to click on them, so here is what can be done:
- When you click on "Combonator" it "opens" - creates 4 virtual poles to the left of it and 4 virtual poles to the right of it. This special poles doesn't have any collision box, but only selection box
- You can than connect poles easily
- After you walk away this virtual poles are collapsed into "Combonator"
- Also when you open combonator a dialog should appear in the corner, it shows you names of each 4 inputs and each 4 outputs. You can change those names when inside "Combonator"
- That would be really great if combinator and/or its inputs had a name or even an icon.
This is essential part for making "Combonator" as a function in programming language.

Function has a name and parameters have names. If all the functions was just items in array (i.e. without names) and they all had just one unnamed param - that would be insane to code like this.

MOTIVATION
The above suggestions would make this entity much more useful because without them:
- You will forget which what does this combinator do (they all look the same)
- You can't implement any logic which have more than 1 input or more than 1 output - that's most logic

But if you implement this you could encapsulate really interesting logic into it:
- A multiplexer (have several inputs obviously - 2-3 inputs)
- A LTN combinator (connects to station and to chest - 2 inputs)
- A combinator for sushi mall (connects to outter combinator, inserter - 2-3 inputs)
- A combinator for effective nuclear reactor (more than 2 inputs)
What I'm trying to say is that "Circuitissimo" is unusable in current state for most logic. Which is really pity because so much work is in it already.

Implementing above will add references from forums like LTN or many nuclear mods and Circuitissimo would become really popular.

What do you need more than the existing 4 wires for?

Also the combinator wires don't work as "inputs versus outputs"...
You can input/output on the same wires simultaneously, or treat 3 wires as input and 1 as output, or whathaveyou.
You can also chain multiple of these combinators together.
And why do the inputs/outputs need names? This doesn't actually do anything.
And why do they need icons? The IO wires are not signals. They're wires.

Multiplexer - 2-3 inputs + 1 output = 4 wires. By your own suggestion you don't need more than what is already available.
LTN combinator - 2 inputs + 2 outputs = 4 wires. By your own suggestion you don't need more than what is already available.
Combinator sushi mall - 3 inputs + 1 output = 4 wires. By your own suggestion you don't need more than what is already available.
Combinator for effective nuclear reactor - 3 inputs + 1 output = 4 wires. By your own suggestion you don't need more than what is already available.

And that's before mentioning, yeah you can actually output on an input wire - there's no issue doing that, it's just doing your combinators correctly.

What i'm trying to say is that your suggestions seem to be founded on thoughts or ideas about how signals vs wires works that are fundamentally incorrect and do not apply to the examples you have given because you have misunderstood how combinators and circuit wires work.
The IO wires are not signals, they are wires.

Changing the number of wires may happen in the future if i ever get around to doing all the graphics and offsets work, but i doubt it. There is little reason to. This also assumes combinators can be given multiple connecting points more than they already have which i don't think is possible, but i haven't checked.
The IO wires are not signals, they are wires.

Did i miss anything?

• You can take graphics from my attempt to do this mod: https://github.com/yuyaryshev/Combinissimo.
  There is entity graphics and connector graphics.

• You are correct: I was misguided by how the combinator looks like (it looks like decider combinator which have inputs/outputs). I'll retry and post more replies about inputs/outputs. Maybe it's not a problem.

• About names - yes they don't "do" anything, but you as player become aware about which side should be used for. If you have say 10 complex-combinators you would have somehow to remember that "left-red input is for the chest, left-green is for the train station, right-red is for input combinator and right-green is for requests". If you have text fields. And you also have to remenber the type of the combinator itself. You cant distinguish them between one-another without names or icons - the all look the same "blue decider combinator".

I have seen some ideas how this can be solved.
- Icons are done in Industrial Revolution - "display entity" - here - IndustrialRevolution_1.0.10\code\entities\entities-display.lua.
- Names and other data can be stored within an invisible "programmable-speaker" - it's the only entity with string field - the field is "alert", and I've tested that in can store 1 megabyte of data or more. So lua table fits in there easily.

Icons on the combinators, just as an indicator/overlay, may be a worthwhile thing to add, similar to how factorissimo does it with a chest on the inside.
We'll see.
I don't see any other issues.
As for assets - nicely done with the 2x2 and 2x3, but again i'd have to check if i can add the wire connection points.

And yes.. it's just a recolored decider combinator, but you can't actually configure it (or shouldn't be able to) because it'll mess with the circuit inside, and opening the menu is hooked.