jj,
Any script that will resize on the fly will require a good deal of server memory. There's simply no way around it. At least not on the server side. The only workaround is on your desktop. Resize the originals and save them in a different folder with the same names prior to uploading. Make them a size slightly larger than your intermediate view settings but well within the size that your server will handle (If you make them the same size or smaller than your intermediate view settings, no intermediate size will be created). Upload these resized photos to your site After you have batch added them, overwrite the original files with your larger ones.
Dennis