The "In God we trust" always reminded me as if it was some sort of reference to Goddess Fortuna who was often displayed on Roman coins. It became a bit of a personal quip to me that Americans seem to have made their money their most revered god and fortune. For that reason alone I would remove the god reference off the dollar.
Also because it is in reference to that one singular deity I find that the phrase can be offensive to anyone of different or no faith. One God, One Country, One people is a near fascist credo in a multicultural country like the USA. Somehow I doubt however that many Americans will agree with me on this point however. None the less I do think most Christians at least tacitly subscribe to that notion.
Giving a privilege has always been easier then to take one away. I think the Christians have been over privileged for far too long as is. Taking their privilege away however will cause plenty of resistance, tantrums and crying about it.
For all intends and purposes the money should be neutral because of the nature in which it is used.
As long it stays legal tender, I'm good. 'As far as I am concerned', they could make special $1.00 issue paper for the season of the year, or birthdays of scientists.
I expect in time, if 'smart paper' become available, there could be free encoded movie/trailers on each one, making them a collector's item. The government could then be 'paid' to print the $1.00 bill as an anvertising platform. Imagine the weirdness that could result, 'Debbie Does Dallas #12", just above 'In God We Trust'. Woow TMI...
Growing up in England, I'm very used to seeing the sign, in small shops, that says:-
In God We Trust
All Others Pay Cash
So having these words on money makes it a tad silly. Honestly, cash is used less and less, these days, and somehow I can't see the credit card companies putting it on their plastic. As cash becomes less and less tendered, I'm guessing the need for anything on a dollar bill will fade. The dollar bills will probably become obsolete without the need for any major re-design. I can't say I really care what the governments write on their currency, it's not like I have to read it. I realise that there is a principle involved, but I have better battles for better principles to distract me.
I think there is plenty of valid religious basis for removing it, and if that aspect of it was pursued maybe it would happen. http://www.youtube.com/watch?v=WtjwdGeQ7kY
Teddy Roosevelt thought it was a sacrilege. I agree, of course, but for exactly the opposite reason.