You'll both need to make a real effort to be completely honest and aboveboard with each other, and not to engage in power struggles or petty ego games. There will be too much tendency in this relationship to threaten, weaken and confuse each other at a deep, murky, emotional level; even 'little white lies' will have a negative effect on your connection. If you aren't careful, you'll both become more and more unclear over time about what, exactly, your aims are as a couple and how you're supposed to achieve them.
Your self-confidence could suffer as well as your general sense of goals and personal power. Since all of this will happen at levels neither of you will fully understand or even be able to pinpoint, dealing with it will be that much more difficult. Just try to be honest with each other at all times, even when you want to save your partner's feelings in some way. And try to let go of your own need to assert yourself at the expense of your partner's needs and feelings. If you can both do these things, this relationship can be a positive experience for you both.