Welcome! It's 100% worth entering your collection here for many reasons. In my case it made me realize I had more cards of certain players than I thought and that made me want to collect them more.
Don't worry about having anything of "huge value" available for trade because you'll be surprised at how many transactions you do where pretty much everything is "lower-end" like base cards. Build up your for sale/trade and wants lists and then you can take advantage of the trade matching system here, plus you'll likely start getting some offers as well.
When you do start trading, please be aware that good communication is extremely important, such as letting your partner know when and how you'll be shipping, whether any of the items they'll be getting have condition issues, etc. A good practice is to write the transaction number on the envelope so it's easy to know which deal the cards came from. And please be considerate and leave feedback for each trade partner.
If you need any help with the site, please reach out in the forums and you're sure to get responses from people that love to be of assistance. The number one thing all new members should know when adding cards to their collections here is that before they assume a card isn't listed, do the following:
1. Search the player's name
2. Click the Filters link
3. Use the card number filter
4. Look for the card in the results
(This resolves many cases where someone thinks the card isn't on the site.)
Enjoy tracking your collection and trading here!