This is huge for me. The ability to create a budget based on tags is the sort of dual-categorization that Mint was known for. It's actually shocking to me how many of the big budgeting tools don't have this as it feels really intuitive for managing your finances with a partner.

+1 for budgeting by tag! I'd like to keep track of a "fun money" allowance and a tag would be a good way to track it while preserving the underlying type of transaction.

I don't know if it fits into this request but I would like to be able to filter or distinguish account contributions in the budget. In my case I have a main account and a "meal allowance" account that i can use for groceries or restaurants/cafes. I would like to be able to see in the budget which of my accounts contributed what for either of these categories without having to duplicate categories for each account.

Even with the improvements in the currently-"beta" new budgeting features, the one reason I have to keep a separate budget spreadsheet is that for some categories (specifically charitable giving) I want to have line-items per recipient, and for some category groups (travel) I want to budget by tag rather than by category. If LM added this feature (and it worked well---no double-counting of transactions, for example), I could finally leave my cumbersome spreadsheet behind.

Yes please! I think there is some features missing when sharing this with a partner, and budgets by tags is a good initial addition :D

Came across another interesting feature request to allow creating a budget for a particular bank account!