When people come to me who are struggling with what God has called them to do & be, I always encourage them to follow their passions and interests (as long as they line up with scripture) and see what God does with it, because that is a part of how God made them.
However, we must always be extremely careful that we are always pursuing the gift Giver, not the gift. Pursuing your passion and interests is a different thing than pursuing a platform. God provides the platform when you are ready, and if someone isn't ok with that, then their heart probably isn't right.
Psalm 37:4 says, "Delight yourself also in the Lord, and He shall give you the desires of your heart"
What many miss in this scripture is this: Where are the desires of your heart fulfilled? From delighting yourself in the Lord. Meaning, God isn't a vending machine giving you whatever you want, when you want it. But, when you pursue Him with everything in you, His desires for your life become your desires for your life and He is able to fulfill them, because your focus is first and foremost on Him.
For example, if you have a heart for healing, read and study all you can. Study scriptures on healing, and read about established healers of the past (like Wigglesworth). Pray for the folks God puts in your path. But don't print out business cards, announce to your pastor or anyone who will listen that you have a "healing gift" (It's all God anyway).
Likewise, if you feel called to preach, again study the Word and other established preachers you gravitate towards. I often suggest even going so far as preparing messages as you get inspiration... even though you have no platform to share them on... you are building your skills,preparing yourself AND growing your knowledge and relationship with God. But, don't go out church to church offering to preach (I've seen it).
If you do things like this, God will provide the platform when you are ready, you won't even have to work at that part, and it will bring Him glory. If you do things like this and you find your passion fading, then perhaps it isn't a part of your calling, but the cool part is you haven't wasted your time because you've learned more about God and your calling.