Two cents from cooking, since our past polls were in a very similar department to your potential ones. The polls may well work out for some amount of time right now - as you say, the site's smaller. But in the long run I'd predict you'll find yourself gradually changing your mind and starting to close them. Old polls still attract new answers. Old polls get used as examples to justify new broad/subjective questions. And new ones get less and less manageable.
Math.SE probably isn't really a great example in favor of this idea; if you look through their big-list tag, you'll find plenty where the voting/sorting has broken down because there are just too many answers, and the early popular ones win out. You'll also find a decent number that are on hold/closed. From what I can tell, the ones that are working out are the ones that aren't actually terribly big lists.
So... it's certainly something you can do, and it's possible it'd attract some users. But if the site keeps growing, you'll almost inevitably find that you have to do a good amount of work to revise your policies and clean up later. Maybe that's a tradeoff worth making, but it's also not a bad idea to try to find other ways to broaden your scope that aren't polls. Maybe you can make product reviews work, or even narrowly scoped recommendations.