Nobody can make this decision for you. Because everybody's preferences as to what and how they shoot and therefore which equipment is going to work better for them is going to differ. Not to mention that budgets vary and what's "worth it" in dollar amounts is also going to vary person to person.

You can peer at test charts. You can read reviews. You could (better yet) actually rent the lens you think is the better purchase, and try it first hand for a week or so to see if it really is what you want. But in the end, this is your decision. You can ask people online for their opinions, but if the decision were objectively easy and simple with one lens being far superior to the other, then one of the two lenses you're considering probably wouldn't exist in the first place.

You are comparing apples to oranges. The 17-55 is a walkaround zoom. A very good one. But it cannot shoot at f/2. The 35/2 IS is a great fast prime, but it doesn't shoot @17mm. The 17-55 is a zoom and will probably encompass some compromises across the focal length range that a prime lens, which can be optimized for a single focal length, will not have. These are two different kinds of lenses, so which one will work better for you depends a great deal on what you prefer, what you shoot, and how you plan to shoot it. The 35/2, imho, would probably be a great deal better for low light shooting, although not as nice as a 35/1.4. Given what you state you shoot, however, a 17-55 may come in handier as a travel lens, but the 10-18+18-55 kit or an 18-135 STM would be cheaper and therefore less of a worry that they could be lost/damaged/stolen while traveling. And it also sounds like your money might actually be better spent on a macro lens, since that's something you know you want to shoot.