Just a vote since I'm seeing a lot of anti-timer sentiment: I like the timer because it creates a conclusive way for the game to end, and causes me to spend a lot less time on the game, I imagine. But I also think it makes sense to have a non-timer mode. It would also be cool to have like 3 shuffles that you are allowed to use. As an exit to the non-timer mode, I think it would be fine to have an "I give up " button.
A problem with timers in word games is players vary A LOT, like a lot a lot, -- no, more than you're thinking now, even after I said that -- in terms of how fast they are at word games.
So a timer needs to either accept that a lot of interested parties will be turned off by it - or must be designed in a more accommodating way.
I also like the timer. Eventually I’d like to do other things and the timer ends the games.
I also love the countdown. Counterintuitively it makes the game less stressful — the counter goes back to 30 no matter what. If the timer counted up, you'd constantly need to care about getting each one as fast as possible, or fret about one that's taking you minutes, etc.
With the countdown, you more want to care about the high level stuff: Keep your brain agile enough to get the next one, figure out more general patterns, ensure you "cover" the promising patterns, notice tough spots (with tons of patterns) where you you'll need to lock in. That stuff is more fun to focus on than speed.
Everyone wants to fail less, sure. It's not surprising people's feedback focuses on the mechanic that made you fail! That doesn't mean changing that bit will make the game more fun.