I'm starting a service business. What are the pro/cons to sole proprietorship vs LLC? I know there is some liability protection of my personal assets in an LLC. Any other helpful hints?

The purpose of LLC, or any type of incorporation is to protect you from law suits. If the service you are providing can damage the customer if you screw up, you could lose everything. In fact that is what LLC stands for Limited Liability Corporation.

Depending on several factors, I might at least wait until 1/1/16.
Starting out, alone, no employees, just file a 1040 as yourself d/b/a (if you chose a company name) or just yourself. Sch C and Sch SE and that's it. Maybe depreciation of equipment, or straight expense if it isn't expensive.
Spend the rest of 2015 preparing for the LLC.