Why are you "concerned" about maxing all of your tax-advantaged accounts?
Each of you can contribute up to $5,500 to IRAs. This is a combined limit between the two types; you could contribute $5,500 to a traditional IRA, or contribute $5,500 to a Roth IRA, or contribute $2,250 to each, or some other combination so long as the total adds up to no more than $5,500.