hmm, i dont know actually... I think that x2 ruins the details when do low-resolution sprites.
details aren't visible at x1 unless you've drawn them, which you haven't. Heck, i need to search for your characters on the screen! And 80% of the image is taken up with rough cutouts.
However, if i wanted bigger sprites I should have done it in the first place and the game have come to
that stage that it will destroy all the code if I make bigger sprites.
Very few games are highly dependent on resolution. Also, game projects are HUGE, this screen and your other sketches are a drop in the bucket compared to the final project. if your design has a serious flaw, which I believe it does (nothing screams NEWB DESIGNERS NEWB DESIGNERS like a huge empty screen), you're still
well within the zone where you can redesign.
I think too that some of the charm will dissapear if it is larger. This is of course not a finished mockup yet and
many other things will appear.
You'll never know until you try! And now is the time I think.
Finally
A game is not all about the graphics, my job is doing the sprites. BUT, a great idea and story is
the MOST important thing. I have played many games with great graphics BUT with a terrible story and it sucks playing
such games.
We're here to help you with your job, and with graphics. People around here obviously have other talents (I am a writer, there are a number of musicians, everyone can at least code a simple website

), but this is a graphics forum. We're not really (and i mean this honestly) concerned with the rest of the game in this setting.
I hope you will enjoy the game anyway 
I will post it here when its done!
we may well, I'm looking forward to it!
even with these small problems 
I think the problem is
bigger than you think, you're so far 5 for 5 against the empty screen style. 5 people hardly make a quorum of the universe, but.. well, I wish you wouldn't brush off critique soo readily.