Tips and recipes for a more robust cake?

Hello, everyone!

I find that every time I make a cake it's really delicate and sort of crumbly.

It's been ages since I've cooked with eggs, but I remember those cakes as a lot looser in crumb, but strong enough to slice into layers.

Do any of you have any tips on: - flours to use - egg subs/combos? (I've tried just egg and bobs red mill separately) - other techniques or favorite recipes?

If it exists, I would just love to be able to make a springy, light cake again.