Ok here it goes, how to tell about it, It just happens that sometimes you don't get to play, not even a bit so how I was going to respond about it.
And then I remembered that in fact some WHFB battles were fought some years ago and I really liked to play my wood elves dragon, it was my firs big model, and no matter what I managed to get him and my treeman in all the games I played (6). so here was part of the answer for me.
but that is a Fantasy setting and we are talking about 40k.
I also got to play some Gothic and besides all the cools units (I have Empire, Chaos, Darl Eldar, Necron and Tyranids) my favorite unites where the pictured next:
My Desolator and the retribution.
now the thorny issue 40K itself:
I haven played a game that simple. so my must have unit is: none, but I like my painted Assault marines so I would like to try them I just hope for a game in the future.