But... one of the biggest complaints about secrets are that they can't be used on your turn. Because of this, secrets aren't as great as they could be.
But, in a way this makes sense since secrets are like "traps" that your opponent wanders into. The biggest argument against secrets is that if you can use them the turn you play them, they'd essentially be spells. Very true.
However, secrets on your own turn did make things more interesting. There were more unique combos and tricks that could be used. This is especially true for paladin, who had many tricks in tandem with the secrets, but also goes for mages too, especially since they're getting a new secret as well (not really for hunters though).
On the other hand, some argue that being able to choose when your secret activates makes it a little too strong; Such as being able to choose which minion to redemption.
Alas, at this current stage with paladin secrets, seldom do they see play except perhaps for Noble Sacrifice.
Here is my suggestion to enable the best of both worlds. This is suggestion is helpful for paladins, but can also extend to mages as well.
Adjust secrets so that they can be used on your own turn but have a one turn 'set-up' time.
This means that the turn you play the secret, it cannot be triggered by yourself. However, you could self trigger it on your next turn, if the secret is still in play.
How will this change things? Not too much initially; on your opponent's turn they will still have to deal with the secret, so if they trigger it the secret will be played like it is now.
However, if your opponent plays around the secret, which is easy to do if they use the process of elimination to deduce which secret you might have, you have the option of using the secret for a combo.
This opens up more options for the paladin (and mage) so long as the secret stays.