You are playing a competitive doubles match. You have been working on several weaknesses in your lessons. You know where you are weak, but you still need a lot of work and practice on them. What should you do? Answer: "Forget about it!"
 
If you are playing a competitive doubles match, not a practice match, you owe it to yourself and your partner to go with what you are already confident in or proficient with. Go with which you are the most comfortable with.
 
Keep working on your weaknesses when you take lessons, when you practice and when you play practice matches. If you are struggling, working on something new and you are not that good on them in practice, its not going to be good in a competitive match under pressure overnight. Be patient and work into implementing your new habits and strategies. It will not happen overnight. You might run out of patient partners while you are transforming.
 
For example: You are a very good baseliner for years, then you all of a sudden you want to serve and volley. This is a long slow process, not something you can accomplish overnight. So, my tip is "Forget about it!" Go with what you already own!
 
Good luck on the Court!