I thought a long time about a mail where someone said that redirects should not be deleted. It is not logic to me that a wrong writing should redirect to a correct form of writing.
Let's take the German word for "German" – language and adjective.
adjective = deutsch
noun = Deutsch (language)
These two would have two different pages – so there's no re-direct possible – you can just add deutsch/Deutsch as related word on the page.
if you take the Italian word:
soprattutto
There's only one way to write it "soprattutto" with lower case "s". At this stage it would be "Soprattutto" that is going then to be redirected to "soprattutto". And the wrong writing should then remain as a redirect? This would confuse people – they could believe that the version with the capital "s" is correct.
Another thing: many people, in particular language students, write this very particular word wrong – they write "sopratutto". Since to easen search you would also allow redirects from wrong words to the right ones this one should then be added? No… this does not make sense.
The only way a wiktionary may be: with correct written words, with correct upper and lowercase. All the other, obviously wrong, stuff must be deleted – otherwise the credibility and the work of many people will become less credible and important.
I know, this is hard word, but the sooner you do it the better it is. All contributors to the English wiktionary should for some days/weeks (depending on the number of actively contributing people) concentrate on the conversion of upper to lowercase where necessary and the admins should concentrate on the deletion of the redirects. When someone sees that somebody still adds with uppercase instead of adding a word just go on his/her user page and tell him/her what to care about and to help with the conversion work. If everyone does this you'll not need longer than a month and than have a neat and correct wiktionary.
Ciao, Sabine