The point is to get as many orders as possible so the style should appeal to the broadest possible number of customers, thus the 1-A is probably the winner. The trouble with custom tweaking is that what appeals to one does not appeal to another.
An SMLE of one version or another is the rifle that comes to mind for most with a soft spot for the .303, and it might be an interesting idea to take some of the elements of our favorite SMLE and have them added to the Ruger, particularly if this rifle could be marketed across the Commonwealth rather than being just a Canadian commemorative. While I don't think a 10 shot mag will work on a #1, consider for a minute the full length RSI version with the half length wood hand guard found on the #5 LE with a straight stock with no pistol grip. Either a tangent rear sight (#1 MK III) or a aperture rear sight and a winged front sight would be an interesting look. A third sling swivel ahead of the trigger guard would work well for a Ching Sling, although most probably wouldn't get it.
Naturally any diversion from a standard product dramatically impacts the price, and the higher the cost the fewer potential customers you could have, but it would be nice if this rifle had more in common with us than simply the cartridge for which its chambered.