Maybe you know this already but the pension amount before 65 includes a bridge amount intended to provide a greater amount up to 65 when CPP kicks in then it drops by approx the CPP amount so your income is level before and after age 65. It's very common in public sector and union pensions.
RRSP vs. TFSA. In general if you expect your marginal tax rate to be higher when you are withdrawing the money then TFSA is a better choice. If you expect marginal tax rate to be lower when withdrawing then RRSP is a better choice. You can check the tax tables at TaxTips.ca to estimate tax rates before and after retirement:
http://www.taxtips.ca/taxrates/bc.htmOAS starts to get clawed back on individual income above about $73k at the rate of 15% of the amount your income exceeds that threshold and it's all clawed back by about $118k of income. Both those amounts get annually indexed to CPI. So unless you expect your income to be above $73k in today's dollars, your OAS won't be affected.
The complicating factor is in the year you turn 72 you will be required to convert RRSP to RRIF and make mandatory minimum withdrawals that start around 5% of the RRIF amount and increase slowly from there each year. So if all your income (pension, CPP, OAS, interest, capital gains, grossed-up dividends PLUS mandatory RRIF withdrawls) is above ~$73k some of your OAS will get clawed back. You can minimize or eliminate that clawback by withdrawing some funds from your RRSP after retirement but before age 72... paying more tax earlier, but less overall. Plus your pension contributions (yours and employer contributions) will result in pension adjustment that will limit how much RRSP contribution room you have anyway.
In my case I maxed out my RRSP, but from retirement at age 60 to age 71 I will withdraw from my RRSP about 1-2% of the total value annually, so by the time I reach age 72 my mandatory withdrawals will be low enough to avoid OAS clawback.
Another complicating factor is if one spouse passes away first, then the RRSP or RRIF amount goes to the surviving spouse, which could bump up their tax bracket considerably and increase OAS clawback. But to avoid that you need to make projections about lifespan.
In my experience concerns about putting too much in an RRSP resulting in higher taxes and OAS clawback are created from fear rather than facts. As I said I have maxed my RRSP and through some careful financial management should be able to be in a much lower tax bracket and avoid OAS clawback in retirement. But everyone's different, so check the following links and estimate your own situation.
Here are a couple of good links:
https://retirehappy.ca/understanding-the-oas-clawback/http://www.finiki.org/wiki/Old_Age_SecurityTaxes are complicated, especially when it comes to investing, so if you have more questions, ask away.