656K in IRA (roughly half Roth, half Traditional Rollover)
71K in Cash Trading account
10k in checking account
Rough FIRE budget: $45k
Unless you have huge gains in the Roth IRA, it appears you already have the ~$225K needed for five years by using cash plus Roth contributions.
As it will be a few more years (at least) until FIRE, continuing with the investment order and growing all accounts seems reasonable.
OP's Roth balance probably includes gains in addition to contributions. We don't know if there's enough based on the Roth balance alone.
OP, I decided to switch from the 72(t) early retirement method to the Roth pipeline shortly before I retired. I did the same thing as you did and totalled up my assets that were available for funding those first 5 years. In my case I was close, so I went ahead and focused on saving in taxable accounts for a year or two which was enough to get me there. But I was making a good income and also maxxing out my 401(k) and Roth IRA because I was saving 60% of my income, so it wasn't a hard decision. If there were a tradeoff between tax-deferred and taxable investments, I guess one would just have to decide if it was worth it, which is a subjective decision. Maybe you can time it and allocate your savings such that you'll hit your FI target at the same time that your 5 year pipeline is funded.
One additional wrinkle that may reduce the amount needed to about 4 years of expenses: Roth conversions are considered made on January 1st of the year in which the conversion takes place, and can be removed and spent on January 1st of the fifth tax year afterward. So a Roth conversion made today (12/18/18) would be treated as made on 1/1/18 and could be removed and spent as of 1/1/23. Note that the actual time elapsed between 12/18/18 and 1/1/23 is a little more than 4 years.