What really came up short was the cash reserve end of things. I bought all the components I needed, but couldn't fund the cash reserve of each piece properly.
Possibly the low cash reserve under UBAHS isn't such a bad thing.
Much of how that strategy works is down to low correlations between the individual components smoothing out the overall.
I think this is reflected in how your IRA has been trading regularly.
As such a 80/20 stock/cash or even 90/10 might be sufficient cash reserve levels to carry across the whole. Which would also considerably reduce cash-drag effects.
I guess the only potential problem is not allowing any one failing segment to burn all of cash reserves under such a shared cash pool arrangement, ETF's reduce that risk significantly.