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I would suggest the same.
However, the addressing of improving her credit while you are waiting for derogs to fall off, can still be a start.
1) The scores FICO8 or Mortgage Scores only obtained here? They can vary wildly.
2) Is her credit surpressed by high utilization? Have her pay it all off except ONE bank card, not retail, if possible. Of that to less than 8.9% of that one card's total line of credit. Never all zero, or you actually are cutting yourself short on points.
3) Derogs- BK? Charge offs, liens, late payments and how recent? Include medical collections.
The more we know what's in her file the better we can direct on the road back to good credit habits.
No arguing that it will help you, no PMI (guessing this will cover a 20% of purchase price). The amount will be based on your income only, your middle mortgage score only. I would advise to only put down enough to not have PMI and the lender can advise on rest, ie approved for up to x amount, any remainder out of pocket, if it should come to that. You always need savings for the unexpected, there down the road, sooner or later will be an unexpected.
As long as you don't need your wife's income to qualify for the loan, I'd suggest you purchase without her on the loan as this would likely save you about a quarter to half point in mortgage note rate.
The VA won't require any PMI so there's no need to use any savings for down payment although you could look into using some of those funds to save yourself on the VA's Funding Fee which is lower with 5% or 10% down payment vs. the no money down.