Vimscript search flicker

"remap the searching commands to my new function. The function is called first, then immediately calls itself
"after the search is finished. This allows me to get the advantage of incsearch being unimpeded by anything
noremap <space> :call DoSearch('search')<Cr>/
noremap n :call DoSearch('search')<Cr>n
noremap N :call DoSearch('search')<Cr>N
noremap * :call DoSearch('search')<Cr>*
noremap # :call DoSearch('search')<Cr>#
noremap ? :call DoSearch('search')<Cr>?

"DoSearch takes a 'command' that specifies whether it needs to call itself again after exeution
function! DoSearch(command)
    "if it has been called with 'search'
    if a:command == 'search'
        "remember wrap set/not set, turn off wrapping
        if &wrap
            let g:waswrap = 1
        else
            let g:waswrap = 0
        endif
        set nowrap
        "set highlighting and our cursorline/column, since cursor not visible during function execution
        "my highlighting for cursorline is light grey
        set hls
        hi CursorLine  cterm=underline ctermbg =0 
        hi CursorColumn   cterm=NONE ctermbg=0
        set cursorline cursorcolumn
        redraw
        "This sets the autocommand CursorHold to execute after 1ms, calling DoSearch
        setl updatetime=1
        augroup flicker_command
            au!
            au CursorHold * call DoSearch('iterate')
        augroup end
    elseif a:command == 'iterate'
        "kill the autocommand and set the updatetime to normal setting
        setl updatetime=4000
        au! flicker_command
        augroup! flicker_command
        augroup end
        "get a character from the user
        let c = nr2char(getchar())
        "while it is one of the search forward/back commands, just keep searching forward
        while c =~ '\v^(n|N)$'
            execute "normal! ".c
            redraw
            let c = nr2char(getchar())
        endwhile
        "revert wrapping to previous state
        if g:waswrap
            set wrap
        endif
        "if we want to do any other key, temporarily turn off highlighting (so I can use :%s)
        let str = ":nohls\<Cr>"
        call feedkeys(str)
        call feedkeys(c) "pass the user's non-searching key to vim
        set nocursorline nocursorcolumn
    endif
endfunction