Extra responsibilities translates into extra experience.The good thingsA lot of things is not established, yet. Which means a lot of room to play and implement your ideas, trying your best to drive the company forward can be a (the only) good cause. You can be as creative as you can. The location is far from town and far from being busy.
The challengesExtra responsibilities does not translate into extra perks or renumeration. You'll just have to accept the only benefit that you'll receive is your accelerated learning curve. Career development is not well planned if not messy. Organization chart is changing at a worrisome frequency. Open feedbacks are limited, ie: my comments on this page got deleted before this.