I completely identify with you. My mind is more of a web then a focused beam however there's no need to attempt to fix it as its what makes us creative. CEO's aren't one trick ponies.
With that said I believe every solid idea deserves its day in the sun. I write a detailed business plan for each venture. The business won,t follow the plan 100% however there is always a plan. I'm never left confused on what happens next. I never work more than 3 projects at a time, and any new ideas/projects get planned out on paper and put in a pending folder.
I then bring on partners and give them equity in the new start up company. I make sure each partner is only used for one business venture there is no over lapping.
I then focus on the business that will potentially start making a profit the quickest and bring it to above net neutral asap. Any downtime that naturally happens I use to work on the venture that can potentially make the most money.
The goal is always to get them to a "safety" point where the market knows our product, we've gotten repeat buyers and we have been acknowledged by competitors as a threat. The most profitable, with the least amount of work gets the majority of my focus, and my partners make sure the business keeps growing.