Bringing back Pietro would cheapen the development Wanda went through due to that event. You can't have your cake and eat it too. Pietro was underutilised in the MCU, but it's very unlikely that they will bring back Pietro, at least the Pietro we know.
Doctor Strange would definitely be able to help in these situations. Depending on what happens, seeing Pietro again might set Wanda off even more. Just because Wanda is stronger than Doctor Strange doesn't mean he wouldn't be able to help, especially considering he's much more skilled and knowledgeable about his abilities than Wanda is. (plus, Wanda is very much so a glass cannon, so it wouldn't be hard for Doctor Strange to knock her out if she went crazy like that.)