Curtain Dilemma

I have a dilemma.

When we moved in, all of the windows in our house already had blinds on them. They're the generic kind that many homes have. While it would be nice to have a blind that's a bit more appealing to the eye, or curtains instead, it's not exactly in our budget to go around recovering every window at the moment. That being said, the patio doors & the front window in our main living area are on my list to update and make our own. Plus, curtains could easily replace these blinds and then the blinds could easily be put back up one day for someone else. The one dilemma is the heat registers. For the patio doors this obviously isn't an issue, however, for every other window in our house it is. So as much as I want to swap out the blinds in our main living area for something else, I have to consider the heat register.

As you can see, the heat register runs the entire length of the window (it's like that in all of the rooms). Where are all the heat registers in the magazines? I'm not too sure I like the idea of having floor length curtains that will be covering the register, especially since we will be closing them for privacy in the evenings and the heat will be on a good portion of the year (we do live in Canada, thank you very much). I'm sure some people would be fine with this, but to me is screams, hazard. So, it's a bit of a dilemma. Finding something a bit more our style, something that doesn't go to the floor and will still look good, and something to fit a rather large window - think, budget.

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What do you think? Would you try this look or do you think it looks outdated and ridiculous?
I'd love to hear your thoughts and what you've done to solve your own curtain dilemmas.