I still wished I could have done more [duplicate]

In this sentence, "I still wished I could have done more", why isn't it saying, "I still wished I could do more"?

Beauty and the Beast season 2 episode 16: http://www.springfieldspringfield.co.uk/view_episode_scripts.php?tv-show=beauty-and-the-beast-2012&episode=s02e16

You okay? Yeah. [sic]

I don't know, it's a little bittersweet, though.

Yes, we finally stopped Sam, but, I don't know, it feels a little hollow, don't you think? We broke up their secret society.

Just take a little bit of digging.

We can put them away for a long time.

Yeah, I still wished I could have done more, though.

That's the old you talking.

The one that used to take the law into his own hands.

I like the new you better.

Oh, you do, do you? Six years is a long time to hold onto all that pain and anger.

Can't even imagine.

I can.

I know the difference in meaning between 'could' and 'could have', but here, I can't seem to get the grammar.

Solution 1:

I take it the character is speaking of something which happened in the past and ended in the past. Simplifying without changing the essential meaning:

I wished I had done more...

This is the past perfect. It describes a completed action before something in the past. I don't know about the show or the characters, but this is something that bothered him in the past. But it's over. He can't do anything anymore.

I still wished I could do more...

is a bit confusing. Do more implies the present, and the ability still exists to act differently. Why would he use the past (wished) for something he could still potentially do?

I still wished I could have done more for her before she was taken away, but I was young and powerless.

All the events are located in the past.

I still wish I could do more for her. She deserves my help. But she's too far away now.

These events are continuing in the present.

Edited to add: In light of F.E.'s expansion of the quoted script, I agree with him that the best word, in context, is wish. There is at least one other grammatical mistake in that script ("Just take a little bit of digging").

However, I don't necessarily agree that "still" implied that "wish" should be used.

^{E.G.: "When I was in school, I wished I could be popular. I wasn't. When I went to college, I sill wished I would be popular. But I wasn't. Then, when I founded (whatever internet company) and became rich, I realized being popular isn't so special.}

Solution 2:

The moment when the person has done the wishing is in the past. Consequently, the second phrase needs to agree in this respect. To illustrate:

• I still wished (then) I could have done more (then), vs.
• I still wished (then) I could do more (now).