Neither submitting, nor interlinking will "guarantee" indexation.

A sitemap can aid in crawl discovery but again, it doesn't guarantee crawling or subsequent indexation.

Your best bet is to use combination all the best practices - good interlinking, sitemap, plenty of unique content on those pages AND most importantly quality backlinks.

Thanks for the tips Omzen I'll study this
Hope you had a great Thanksgiving

Multiple submissions for pages on the same domain MAY be interpreted as spam. I don't know what the current take on this is by Google and Bing but a few years ago it would have been a very real risk with some search engines.

The best way to get inner pages indexed is for external sites to link direct to those pages.
1. Many sites will only link to the home page
2. You are going to dilute the value of inbound links by having them spread around the site.

I built a good set of long tail results on one site by having just two possible landing pages, one relevant to generic sites on our topic and one for sites in our geographic region. That fitted the site topic which was for a regional arts organisation.

Often the internal linking pattern needs to be a compromise between what's best for visitor navigation and how best to flow a lot of pagerank juice to the most important pages. You need to consider both aspects.

Thanks for all your info your guys are great!