you have a 5 speed trans brother, all 3g rams do, the early 02-03 rams had a 4 speed but a simple computer swap gave you that virtual 5th gear that we all have, but ill tell you this about gears, Lil Ram is lifted with big tires and all of that, his 3.92 gears are not much different than your 3.55s you are running on your truck after you add in all the extra on his truck, those gears just make it much easier for the little 3.7 to get his truck rolling...
in your trucks configuration, id stick with your 3.55s, i wouldnt touch a 4.10, now if you plan to lift your truck on 37s then by all means go for that kind of gearing, hell Lil Ram would probably benefit greatly from going to a 4.56 gear with his setup.
but the problem is with your small tire size and having the little 3.7, you are going to run into highway driving problems just like my 3/4 ton has, my 08 has a 4.10 gear ratio and going down the highway im pushing 2500 RPMs at 70-75 MPH, the little 3.7 is going to run higher RPMs than the hemi as it is, so your truck will be great around town and probably ok up to 60-65mph.
but that 3.7 is not a strong motor by any means neither is its big brother the 4.7, and i would be terrified of running that motor at over 2 grand for any long length of time, ive had and seen too many of them fail pre-maturely so i wouldn't want to put extra strain on it for no reason