Does a strategy should be complex or easy and simple to be achieved ?
Of course it should be simple and achievable so that it can be implemented through the tactics within the realistic timelines.

But, how can you ensure that your digital strategy is not complex and is simple enough ? Actually, the answer is directly related with the targets you want to achieve in long and short term through your digital tactics. If you have the enough capabilities or can have them to implement the tactics, then you are on the right track. But, if your digital strategy is not fully aligned with your marketing objectives or it is not achievable or the digital tactics are not easy to implement, then, you should start thinking about the simpler realistic alternatives.
Do not waste your time with complex, unachievable strategies and the tactics around. Start with the simple, improve it within the time. Digital space has a lot of instruments for every stages of your digital journey.