Until the last week, I used RubyMine to develop Rails. I know that it has a vim plugin, but I worked on porting my development to vim and tmux. I do not want to continue to use the mouse, and VIM gives me more flexibility. I found plugins and workarounds for almost all the functions that I care about, except for the "interpreted automatically completed" functions in my first screenshot below. RubyMine interprets the entire rails application and offers suggestions for sorting by relevance (as you can see, it shows me the instance variables and methods for the class in question and the modules it includes) THEN shows the (less relevant) methods available on the Objectclass. It also shows the signature of the method when it is.
Also, in my second screenshot, you can see how RubyMine offers autocomplete for the main Ruby classes.
Compare this to the bottom screenshot. I have a completion, but there is no way to find what I am looking for. I use the ctags, YouCompleteMe, vim-rails, vim-rubyand I also tried to install eclimto know, does not matter.
Is there a plugin I missed that can improve my autocomplete? It doesn't look like RubyMine is doing something super insane. prycan give me the same “power” if it works in the same “context”.
First screenshot (RubyMine is interpreted automatically):

Second screenshot (full RubyMine Core Ruby classes):

Third screenshot (vim omnifunc + ctags):

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