I use ctags, taglist, etc., to have auto completion in Vim. However, it is very limited compared to Visual Studio intellisense or Eclipse auto-completion. I am wondering whether it is possible to tune Vim to:

1. Show auto-completion whenever . or -> are typed. But only after some text that might be a variable (e.g. avoid showing auto completion after a number).

2. Show function parameters when ( is typed.

3. Stop removing the auto completion list when some delete all characters after . or ->: When I enter a variable name, then press . or -> to search for a certain member, I frequently have to delete all the characters I type after the . or ->, but this makes Vim hide the auto completion list. I would like to keep it visible unless I press Esc.

4. Showing related auto completion: When I type a variable and press ^X ^O, it usually shows me all the tags in the ctags file. I would like to have it showing only the tags related to the variable.

Thanks for the help.

EDIT: Some people are voting for this question, but no body seems to know the answer. So just wanted to mention that you don't have to provide a complete answer; partial answers to any of the mentioned points would be good also.