(You) are almost there and not grandstanding. Shifting to Joint Budget Resolution on a biennial basis is a good idea - and changing the budget process as part of an eventual tax and budget deal is not unheard of. Automatic expenditure is also a good idea if there is no budget at the end of the year - which a Joint Budget Resolution makes possible.
I would limit the President's initial budget submission for the two year budget to Joint Budget Solution totals only. After the JBR passes, the White House would submit detailed appropriation numbers, entitlement and tax law changes, major regulatory actions (for amendment) and a current services budget showing how current law fits into the JBR totals. If appropriations are not passed or are vetoed, the JBR current services numbers become law automatically, forcing the appropriations committee to work with the Administration and get its work done on time or resort to supplemental appropriations after the fiscal year starts.
P.S. I would also consider setting up a Joint Budget Committee - however the failure of the Joint Select Committee to come up with a package mitigages against that.