Several dog breeds are quite useful as draft animals. St Bernards and Newfoundlands both can outpull a Husky. Saints regularly pull 10-12 times their own weight in pulling contests. This is around a ton of concrete blocks on a sled on dirt with no wheels! What's more they love to do it. Bernese and Greater Swiss are also traditionally used as draft animals.

I have four huskies that pull a racing sled in the winter, which is a little like vehicle racing with the accelerator nailed to the floor. I wouldn't dream of using one to pull me on rollerblades in other seasons as that would be a recipe for broken bones, especially in the city. Using a scooter with one dog is much safer as the rider can jump off if necessary (by which I mean plant their feet on terra firma while still holding on to the scooter and attached dog). I wouldn't do it in a built-up area though - there are too many distractions that could cause a husky to shift direction abruptly. Training helps obviously, but even well-trained huskies have a mind of their own.

Huskies were bred for food-efficient pulling power and so could be very useful for getting around in winter if the roads were no longer plowed. (The inevitable falls hurt much less if one is landing on snow.) For summer pulling on rollerblades I'd recommend a breed which is more likely to have the word 'stop' in its mental vocabulary. Also, choosing a breed less likely to overheat in summer would be advisable. Huskies spend most of their time sleeping when it's hot.