After maxing 401k, is it okay to go straight to taxable brokerage?

I'm (33F) maxing out my 401k, and still have a chunk leftover for investing monthly which I'm putting toward a taxable brokerage. No kids yet but hoping to in the next few years, so trying to use this time to invest as wisely as I can. I think my current approach has me on track for my FIRE goal, but the tax side of things is definitely a blind spot for me. I'm worried I'm setting myself up for pain later by not doing more in tax advantaged accounts, but I have the hardest time understanding how to actually implement a mega backdoor roth or roth conversion. I have about 10k in a traditional roth from early in my career, but haven't contributed to it since.

I'm considering a one hour advisor session to help me figure this out if tax advantages really are critical for the FIRE life, but wanted to ask the fellow FIREyFemmes first if y'all think I can I get away with just the annual contribution to 401k + taxable instead. Thanks!