“I do think keeping a clean house is important, but don’t let it limit you.” 
A missionary wife should be involved in ministry. Just as any Christian woman should want to serve the Lord and be involved in good works.
One might say that it is hard to be a housekeeper, wife, mother and be involved in ministry. I agree that it most likely is, from what I am told (especially with young children, it is hard to get out of the house and do ministry). But you can be involved in the following ways without ignoring your first priorities:
1) Disciple your children. A missionary wife should see her children as her “disciples”. She has the unique privilege of teaching them the ways of the Lord. Don’t ignore this great opportunity. Don’t ignore teaching your children the Bible so you can teach someone else the Bible.
2) Take your children with you. Serve the Lord with your family. Show your children by example what it means to joyfully serve the Lord.
3) Invite others into your home. “When we invite others to our home they are not only ministered to by our conversations, but more so by what they see.” You are showing them what it means to be a Christian mother and wife. You are a living example of Christian womanhood. They can see and observe you. Also, you can study the Bible with others in your home etc.
Know that your role as a missionary wife is a very important one. You have influence given to you because of who you married. You will be watched more closely than others. You have the opportunity to make a difference and be a light in the world. As you desire to do your best, remember this quote by a missionary wife:
“You are no less a missionary than your husband if you are not out in the hospitals, villages, schools, or businesses everyday. There is so much that you can do. Keep in mind your priorities and that you are a model of a Christians family to a lost world around you, and rely on the sweet, sufficient grace found only in Christ for your strength and fulfillment. Do not rob your marriage of what reflects Christ and makes for peace. Do not rob your children of the chance to be nurtured at home under the care of their mother and ways of the Lord. Do not rob the lost world around you from seeing a Christians family the way that God designed it to be seen.”