What’s a good synonym for "system", as in a set of things that can be combined?

I am searching for a word which embodies the total of parts (things) which were designed to fit together. For example:

A screwdriver “kit” commonly contains a screwdriver handle and screwdriver bits, potentially drive guides, etc.

While the individual pieces might be called components or parts, how can we refer to the whole?

In the example I gave above, kit is already pretty good, but it is a little bit too physical and with too little emphasis on the ability to be compatible with each other.

Some ideas I’ve had so far:

  • System — Too generic, fallback if nothing more specific comes along.
  • Set — Too generic, contains a nuance less "intent" of being put together, but less ambiguous connotations when compared to system.
  • School (as in school of thought) — A little bit too lofty or ephemeral. Too close to animals (school of fish)?
  • Nomenclature — Would be ideal if there were such a thing as an *objeclature for objects rather than nouns. Brings together the notion of being intentionally designed or selected with the notion that it is more than two items.
  • Accessories — Would be great if there were a primary item that stood out among the others. Yet, as with the screwdriver example, I want to include the screwdriver itself in the set.
  • Component set — Wordy but otherwise pretty fitting.
  • Assemblage — Sounds like the parts were already combined together rather than being bundled together for being assembled by the user.
  • Series — Could be fitting, but has a strong temporal scent. Seems to indicate more than one in a line of things, not intended to complement/combine but to replace. Do you like our new Screwdriver Series X500?
  • Array — Seems to implicate an individual number of items being positioned (that is, located) next to each other rather than the possibility of combining things.
  • Collection — Good emphasis on being designed from a single hand (e.g., our collection of excellent wines), yet unclear on whether the individual pieces would blend or work together.

I could go on, but I hope you might have better ideas already.

If possible, the word should carry some connotations of:

  1. The individual items being designed together.
  2. The items go mechanically together.
  3. The items belong to the same manufacturing process and level of quality.
  4. The items being self-contained and needing no outside additions or extras.
  5. The items being still separate and not assembled into a whole
  6. The whole being of value (kit, for instance, sounds a little cheap).

How about set?

From Merriam-Webster:

set: a number of things of the same kind that belong or are used together

Set carries the following connotations specified by the OP:

  • The individual items having been designed together
  • The items fitting mechanically together
  • The items belong to the same manufacturing process and level of quality
  • The items being self-contained and needing no outside addition or extras
  • The items being still separate and not assembled into a whole
  • The whole being of value ("kit" for instance - sounds a little cheap)