Without knowing a lot about your company, the fact that innovation is one of your core strengths, leads me to believe that you have a transformational mindset.
There are "Transactional" CEOs and "Transformational" CEOs, and few companies in existence these days will go far (or even exist much longer than 5-10 yrs) without a transformational CEO.
While transactional leadership is needed to maintain the normal flow of operations, transformational leadership is what will help your company evolve, and transform the brilliant innovations you have into competitive advantage and business value.
So ensure your potential CEO can articulate their approach to "business transformation".
Ask them to talk about how they see innovation and digital technologies contributing to business transformation. Ask them to explain how they envisage involving your staff and freelancers in the transformation process, in the company's strategy and to tell you a few stories about how they have already successful done this.
Cultural intelligence is critical, and it is important that your prospective CEO understands the Eastern European business and social culture. I have known too many American execs come to live in Eastern Europe (Prague & Katowice) and work against the culture, and not last very long - with both the company and the country!
Aside from the good free advice you can read around the net from Harvard, McKinsey, etc; I have tried to give you a few recommendations that are particularly relevant to your unique circumstances.