I know just what you mean. Keep in mind that most freezers work better with more air circulation space between containers. Because of that, I mostly use Ziploc or Glad PP #5 ”disposable” but highly reuseable, DW safe, stackable. Glad has had a couple sizes of rounded rectangular freezer specific containers, but I haven't bought any recently and don't know if they're still in the stores. The reason I like them is they're less likely to shatter, or even break, when dropped, frozen solid, on the garage floor. Both brands are shaped with space left between them.

For stock, however, I got a bunch of different small sizes of containers by Arrow Home Products. They're square in cross-section, and vertical, with just enough angle to be stackable. They remind my of my mother's old Freezette containers from when I was little. Arrow are thinner and modern food-safe plastic. The tops need a bit of care to make sure they're seated correctly, but the do seal well, though I think the roll-edge snap tops of the disposables are a bit tighter. The Arrow tops can also warp a bit, being softer, but I've never had one become unusable. I only have a few rounds of experience with them though. They are by far the most space efficient I've seen. I think the Arrow website has a store finder.

For freezer to microwave, I use glass designed for the purpose. I don't do much of that. Generally single portions of M&C. Never in the garage freezer. They'd shatter just as badly in the kitchen if dropped, but easier to clean up. And glass doesn't transmit the cold as much to numb one's hands. They're pretty space efficient, however, other than glass being a lot thicker.

Ziploc does make pint freezer bags, but good luck finding them! Maybe your local store can order them for you. If there's a restaurant supply store, they may have small sizes. Or, if you have a sealer, you can use a bag roll (sealed on two sides, cut the length you need, seal the openings on two sides yourself). I've cut them up the middle, too, to make little bags I sealed on three sides. But those are expensive and not reuseable.

Good luck with the Quest!

Those Gladware-type storage containers come in smaller sizes and are pretty easy to find at the local grocery chain around here.

Like these; there are many other smaller sizes available:

GladWare Mini Food Storage Containers | Small Round Food Containers, Mini Round Food Containers Hold up to 4 Ounces of Food | 4 oz Containers with Lids, 8 Count Set - Walmart.com

Gladware - Mini 4oz - Mini Round - 8ct - Walmart.com

I use small glass rectangles and squares from Glasslockusa dot com. The baby size is great for small amounts of condiments.

I use a foodsaver and can make whatever size bags I need. Yes, they are a bit more expensive, but things last so much longer! The grocery stores have a bunch of different sized bags! Freeze flat and stack!

Do you have Ikea in the U.S.? Their bags are cheap and they have all sizes.

Pint freezer bags used to be standard in stores here but a couple of years ago began to be hard to find. I use them all the time for a great many things.

We have Ikea but not close by. I live in a rural part of a rural state. Ikea is another state or two away. Sometimes I miss living in NJ where ones American right to shop day or night is taken much more seriously.