We're a family a dual citizens (moved from the US to Canada a little over 4 years ago).
Our taxable investments are held (in USD) in US-domiciled ETFs with Questrade. Tax sheltered (e.g. RSP) is in CAD in Canadian-domiciled ETFs with Questrade. Canadian ETFs in a recognized retirement account (e.g. RSP) don't trigger PFIC filing requirements.
A TFSA would, though, since it isn't recognized in the tax treaty. You could still technically do a TFSA as a US citizen, it's just more complicated -- you'd have to report gains and losses to the IRS each year AND you'd want to avoid PFICs, so keeping it in USD and investing in US-domiciled ETFs is the way to do it. As other folks have said, Questrade is good and provides 1099s on taxable accounts. I'm not sure if they also would provide these for TFSAs (though that would make things easier). Regardless, I'd keep my TFSA simple -- 3 or less ETFs, buy and hold.
When I reached out to Interactive Brokers about making an account, they were not open to US citizens who are resident in Canada. That was 4 years, ago, though, and I never followed up.
For us, currency conversion has not been a big deal, except for when we bought our house, as our taxable account was always in USD. When we bought our house, we used Wise. Norbert's Gambit (so far) I haven't bothered to do it. In my opinion, DLR would absolutely be considered a PFIC, so I wouldn't use that -- Royal Bank should be OK.