Many folks don't notice difference in crank lengths.
Saw one tandem with 175 front and 170 rear. However shop mechanic (?!) had mixed up the crossover tandem cranks . . . nobody riding it had noticed.
Longest crank arm lenghts was custom built 220mm for a fellow that's 6'7". Had to utilize higher than normal BB setup.
We've been using 170s front and rear for decades, even with a height impaired stoker (4' 10 3/4" tall).
If your body/mind feels better with the switch, then do it!