@blueberry25 I think with the plan as spec'd he's better off maxing Roth and then just putting other savings into a standard investment vehicle. That allows him to build maximum tax free and then access the rest before age 60 so he can retire at 50.
Now,this does depend somewhat on actual gains and investment style. If op is aiming for long term capital gains with "buy and hold", then there's not much point maximizing standard 401k over Roth. The big benefit is tax deferral on the assumption that retirement income/tax bracket will be lower. But op is aiming to have equal income in retirement, so the tax benefit is basically only realized if 1. They are an active investor (short term gains) and 2. Nominal tax rates don't increase in the next 30 years, which is possible but unlikely imo.
Also, any money in retirement accounts will be subject to RMDs, so could affect taxes adversely depending on the specifics.
All THAT said, I think odds are 50% at best that Roth accounts keep "tax free" status for the next 30+ years. I think there will be a lot of people that don't have one that get envious.