Try a backpack with small Plano boxes in it. Set up the boxes based on targeted species or lure types, then you can take out unwanted tackle if you’re not after that species or expected to be using a certain type of lure. This will limit weight. The backpack will fit a lot of places that a rectangular semi-hard-sided case won’t. Many of the soft tackle bags have pretty firm sides, especially when cold.
Otherwise, check out the Falcon V6 Tackle Bag. It’s very heavy duty. I use it in my boat for organizing miscellaneous stuff that’s being used a lot: Senkos, jig trailers, etc. I tried using it for ice fishing, but I prefer the backpack method I previously described.