how to avoid duplication when object becomes subject in second half sentence: X has an Y, and this Y does Z

(1) A software project should comprise a test suite, and this suite should be ever growing.

How to avoid the duplication of suite?

(2) A software project should comprise a test suite that should be ever growing. -- not quite the same, one statement instead of two.

(3) A software project should comprise a test suite, and that should be ever growing. -- is this unambiguous? better than the original version (1)?

[edited:] my concern is not so much about style, but rather about grammar and semantics: how to get rid of the duplication with minimal transformation while maintaining all the meaning and nuances of (1).

Solution 1:

One concise way to achieve that is to transform the predicate adjectival part into an attributive one, as shown now.

• A software project should comprise an ever growing test suite.

In the way of keeping to two separate specifications there is also the possibility of using the idiomatic phrase "at that" with pronoun support (one), but if it is not considered informal by OALD, it is so by the Cambridge dictionary. It follows that you can expect it to be at least slightly informal.

• A software project should comprise a test suite—and at that an ever growing one.

• A software project should comprise a test suite—and an ever growing one at that.

Pronoun support is also possible with the second form, where no ambiguity can result from context.

• A software project should comprise a test suite that should be an ever growing one.