Unless you own a super common word or group of words as .com; it doesn't make too much of a difference. Only enthusiasts will use a smaller service, regardless of its usefulness and will be ok googling for a domain or entering a less common TLD. Wait to see if it develops and if it does, use your profits to buy the right domain for more casual consumers.

I'd say best you can do is make your site https and responsive and make sure you have all relevant SEO data to increase its indexing performance.