Welcome to the Q&A Forum

Yeap, google should be crawling all your site naturaly. Remember that bots have a finite time to crawl your site. It might be that there not enogh time for all yout images. Even more, if you want to be stric with only high res images indexed, that's the main reason to use sitemaps. And yes again, use different sitemaps, ona for images and one for pages.

Hi there Well, here is my thought: Let's say you had a domain old-domain.com with bunch of good backlinks; You got rebranded (or whatever) and got new domain new-domain.com; You did a 301 domain redirect from old domain to new domain (which is a well known good practice and recommended by everyone, since, as we know, 301 pass goodies along); Would it count now that you have a backlink (any benefit) from your old domain? I don't think so. Otherwise everyone would buy 10000 domains and did 301 redirects from them to their main domain, right? So, to me it seems that shorteners have the same logic. Hope it makes sense