Missed approaches are based on 15 degrees AoB anyway. If terrain is an issue, like CMF, then speed and AoB requirements are stipulated.
However, if you want to minimise your turn radius then -
Vfsquared
TAN AoB x g
- will give you the answer.
Best climb rates and angles aren't always achieved by continuous climb either and may, occasionally (depends what you're flying of course), involve descending or flying level to achieve a higher indicated speed before recommencing your climb. So sometimes it may be prudent to accelerate and clean up rather than continue climb with extra drag.
There are too many unknown variables in your question to accurately answer it.