The trinkets had the negative effect versions removed a few years ago, which was a welcomed change.

To help further their usefulness and desirability, can the length of those effects be increased?

Many are only 1 to 2 minute effects. Increasing them to 15 minutes at a minimum, to 2 hours would go a long way. I do not think people think of them as trash any longer, but not many use them since the effects are often short.

I would suggest increasing the effects timers as follows
Current timer Suggested Timer
1 to 2 minutes 10 to 15 minutes
5 minutes 30 minutes
10 minutes 1 hour