I'm a bit confused. You said water backup, do you mean sewage line blockage problem?

If so, preventing the problem is much preferable to adjusting the furnishings. What was the cause of the original stoppage/problem? Find that out and simply prevent it from re-occuring.

General guide for drains---no animal waste---like left over meat scraps/grease/bacon fat/etc. No leafy vegetable waste---unless you have a disposer.

No potato peelings---period, disposer or not.

And, no hair/etc.

Now, about the sink---if there is a floor drain in the basement, and there should be, that is the first place for a backup to surface. The only warning would have to be a self made system---in sink float connected to some kind of alarm---and that would pretty much negate use of the sink.

Does not make much sense to reinstall carpet if you anticipate another problem---will just recreate the initial problem.

If any drywall was affected by the backup material, that needs to be replaced and framing/insulation inspected.

If the repairs have both been through insurance, you can look forward yo a restriction of coverage and an increase in premiums or outright denial.