I would like do it something like this:
macro pushx arg
{
cont = 0
if arg eqtype 32bits
cont += 4
else if arg eqtype 16bits
cont += 2
end if
add ax,cont
}

use32
macro pushx arg {
local ..override, ..count
virtual at 0
  push arg
  load ..override from 0
end virtual
  ..count=2
  if ..override <> 66h        ; no size override prefix - has to 32bit
    ..count=..count+2
  end if
  add eax, ..count
}

  pushx DWORD 0               ; add eax, 4
  pushx WORD 0                ; add eax, 2
  pushx DWORD [0]             ; add eax, 4
  pushx WORD [0]              ; add eax, 2
  pushx eax                   ; add eax, 4
  pushx ax                    ; add eax, 2