Does buying through a pension negate the tax benefits?

[Jeff Ju]

I've got an accountant who has been encouraging me to maximize contributions to a defined benefit plan despite my goals to invest in real estate. 

While I appreciate the tax deferment, I'm concerned about the following two points that I am hoping to get clearer answers to here. 

1. I hear that one of the best things about real estate investment is the tax benefits - namely, depreciation. Since the income of the retirement plan is tax-free, doesn't this make depreciation a moot point?
2. Leverage seems to be a key ingredient of real estate; however, this creates a taxable income (unrelated taxable business income) in an investment vehicle that has an otherwise tax-free environment. 

So is it better to provide hard money / private money to investors through the pension? 

For real estate investments, perhaps stop stuffing the pension and, instead, pay a little more tax up front on the personal side and use that to invest in real estate instead?