Should invest in taxable brokerage or wait for new tax year for IRA contribution?

I maxed out my IRA for the year, and after setting aside money in fdlxx for emergencies, I have about $2500 leftover. I don’t have access to a 401k for at least another 6 months (I’m in the process of going temp-to-perm and the company has a 6 month wait time). Should I put the $2500 in my taxable brokerage account, or wait until 1/1/27 and put it in my IRA? I currently have $7700 in the taxable brokerage invested in VTI. This cash would be used to buy VXUS to add some international exposure. The purpose of this account is to use it as a bridge until I hit my retirement withdrawal age in about 24 years, and as an ultra-emergency fund.

I’m going traditional because (1) I live in NYC so I get a better tax break now (2) doing so lowers my AGI for student loan RAP repayment certification and I can save myself 1500-2000 a year in payments (3) I plan on retiring abroad and a lot of countries don’t recognize Roth contributions.

Any input would be greatly appreciated!