Realistically it won't make a difference since you have an unlocked bootloader anyway and you won't be able to pass strong integrity with it unlocked regardless. It just makes using some apps a bit of a headache, but if you can deal with playing cat and mouse with safetynet fixes it's not really much of an issue.

As far as apps, I recommend the gappsmod to get the Pixel dialer features and AdAway as a baseline, but it really depends on what you want to do with the device.