Speedsters are a pretty big thing in the DCU. Marvel only seems to have Quicksilver. In that case, why isn't he featured more, assuming he is similarly powerful to Flash, who is a top tier hero in DCU?

i would LOVE for this to happen

Because he's not in any movies atm ;)

Because he's a part time villain and he's just not written as a very strong character if you add in his emotional state. I wish they would take advantage of his connection to Magneto and the X-men more rather than always writing the daddy issues involved . The Flash tv show wasn't exactly the best thing ever lol.

He's been given too many second chances already, at this point I feel they should just let him be a villain.

He's also not similarly powerful to Flash either, he is far slower. Marvel does have some other speedsters though, who I'd love to see get more of, such as Makkari, who I believe is lightspeed, and Northstar and Aurora are close.

There's also Monica Rambeau, although she has too many other powers to just be considered a speedster

They have the tornado guy too if he counts... The one that spins so fast that he's a living tornado. Anyway I wish Marvel did have a few more Quicksiver/Flash types but as you can tell Marvel just doesn't seem to care much for them.

Good question

Although Stan Lee had big plans for Quicksilver from the beginning...meaning, he always intended him and his sister to become good guys and join the Avengers...I always like Pietro as a bad guy or a gray area character, like he is now....being a super hero doesn't work for him
 
I think he should start a new brotherhood or something

It's not about their power, it's about their character.

He is, or at least was for some time from House Of M on up. I think personally what happened is his story and character became really convoluted (considering his tampering in House Of M, loss of powers, possession, issues with the Inhumans, issues with Crystal, lies, frequent turbulence over several different titles in a year around Dark Reign and Siege, ect.) and writers may be a little cautious about how to approach his character at this point in time, and now feature him less prominently as a result. As a guess mind you, just noticing how outgoing he was for a couple years than how he was pulled back into more of a background character recently.