I would keep it where it is. You have good fund options and your husband is probably getting pretty close to the income the limit on being able to put money straight into a Roth IRA even after deductions for health insurance and maxing his 401k. A few more raises or if you pull in some income and you'll be over the $186k AGI limit. If you want to be able to do a backdoor roth it will be good not to have any existing traditional IRA balances.
He actually already went over the limit. Our plan was that he wound fund a regular IRA as a spousal IRA for me each year in addition to maxing his 401K. I think we decided against doing Roth conversions because hopefully our retirement tax bracket is going to be less than 28% although who knows.
You're probably right that you both went over the limit for this year since you had some income this year. In the future, if your husband continues to make $200k, maxes out his 401k, and probably has some health insurance deductions then you should be under the $186k limit, unless you go back to work and push that up. What matters is not gross income, but rather Modified Adjusted Gross Income (MAGI) which is your gross income reduced by pretax payroll deductions like 401k contributions and pretax health insurance premiums.
Remember that even without a retirement plan at work, since your husband does have a retirement plan at work, your ability to deduct a traditional IRA contribution begins to phase out at $186k (and goes away completely at $196k) as does your ability to contribute directly to a roth IRA. See
https://www.irs.gov/retirement-plans/2017-ira-deduction-limits-effect-of-modified-agi-on-deduction-if-you-are-not-covered-by-a-retirement-plan-at-workOnce your MAGI is over $196k you will no longer be able to deduct any of your traditional IRA contributions, and you won't be able to make direct Roth IRA contributions, so the only option left is to make non-deductible traditional IRA contributions and roll those over into a Roth right away. This is what's known as a backdoor Roth contribution. Having previously made deductible traditional IRA balances complicates this process and will require you to pay taxes on some of the conversion which is why I suggested it might be best to keep your 401k where it is.