RSSB
Return Stacked Global Stocks & Bonds ETF
stock BATS ETF

AVGV would be a good one to pair to with VTI/VXUS/VT unless you wanted to dial in specific US/international allocations or focus solely on small value. It holds basically every value fund Avantis has. I use it in my TIRA with RSSB to hold basically every equity/bond fund category I want with minimal tinkering.

Too tired to explain how to best use LETFs, but if you want an all in one solution, it would be PSLDX, NTSX/NTSI, or RSSB.