Would be nice to have a secondary email address spot on the Personal Information page of T1. I find I want two listed for many clients. I have been using memo’s for this but if another spot could be added I would find that useful.
I find the second address is often one for the client’s employer. Because of privacy concerns with employer access to the email account, I won’t use those without express consent from the client after letting him/her know of the privacy concerns.
Despite secure alternatives provided, it is amazing how many clients still email T slips with a FULL SIN. 
Additionally, some of my clients not only send me slips & the like, via regular email, even though I provide them a free guest user account with e-courier, but also get upset when I absolutely refuse to reciprocate in the same manner.
They just don’t want to bother with the secure alternative … too busy on social media!