What is the best way to store homemade sauces?
If you apply a best-case/worst-case/likeliest-case approach to estimating when you will be using the sauce, you will want to maximize food safety (i.e. shelf life in fridge is shorter than in freezer or in a jar), time to prepare (i.e. defrost), and time to store (i.e. jarring).

If you have a given sauce X, all risks being equal, and you want to store it for one to four weeks, I would recommend freezer bags for the following reasons:


Food safety: a sauce will last a few days in the fridge, it will last weeks and months in the freezer or in a jar
Time to prepare: having your sauce in the freezer means being prepared in advance to use your sauce, and defrosting the night before, in the fridge or a jar you can just open and use it
Time to store: in the cases of jarring/canning, the storage process is cumbersome for a one-off sauce that is not being stored in multiple quantities, in a pyrex in the fridge, or a ziploc in the freezer, it just takes as long as pouring it into the container


Jarring will have the best shelf life in all likelihood (assuming you don't contaminate your jars, or end up with exploding glass), as freezing your sauce may cause a separation, and in the fridge it will pose a health risk quickly.

Storing sauces in securely closing plastic freezer bags, in the freezer, is my preferred method in the scenario you have outlined as it allows you to portion out smaller quantities, has a good mid-range duration of food safety, and isn't terribly likely to cause any flavor issues within three to six months, let alone in the scope of one. As for defrosting, it sounds like you are already planning out your dishes, and putting a bag of sauce on a plate in the fridge in the morning wouldn't be problematic.