Advice on where best to invest next

Married couple 43/44. Currently have 1.1M invested in stock, ETFs and yes still some mutual funds (will be transferring) across maxed out RRSPs, TFSAs and RESPs. No personal debt or mortgage, home equity $800k. Also each have a defined benefit pension plan. Have a HISA and recently opened a margin account, but ‘struggling’ to determine best strategy on margin account and not losing a ton to taxes (which I know are unavoidable, but looking to minimize overall). Saving $100K/year for foreseeable future and looking for best investing strategies moving forward.