Your IRAs have such low contribution limits. Our RRSPs here in Canada allow up to 18% of your total income or about $25,000, whichever is less.

And our TFSAs, which are equivalent to the Roth IRAs that you linked to, have a slightly smaller yearly contribution limit, but in our case it's cumulative, so if you contributed $5,000 but withdrew it all for something, the next year you could contribute up to $10,000, to make up for the $5,000 you withdrew. I don't see any indication you can do that with IRAs.