I'd buy VCN.TO in your tfsa, to avoid withholding tax.
I'd do VO and VTI for RRSP, using IKBR for conversion to USD. Again to avoid withholding taxes, and to provide diversification.
Then your margin account do XAW.TO.
This is easy and avoids all the pitfulls of taxation while optimizing diversity. Though you can do some XEF.TO if you want more Europe exposure in your margin, since your RRSP is heavily into US and you want to keep it relatively balanced. Doing 5-10% KILO.TO for disaster risk can also be wise, as gold tends to spike when the stock market bailout comes in.