confusion regarding image info and repetition

This is a general question regarding the use of WordPress and understanding a bit about all of the options and pitfalls of SEO.

The Rub:
In trying to read and watch as many videos and dissect as much information about SEO and now my first attempt at WordPress, I have, for most of you, a simple question.

Where is the following setup will I get penalized for repetition and when is it OK?

The Setup:
1.) Images in the media library are all set up to have filename eg. big-white-house.jpg (my understanding at least for now is that this is the accepted format).
2.) They all have a ‘Title’ (*that is similar or the same but without the “-“)
3.) They have an ‘Alt-tag’ (*Again a copy of the title exactly)
4.) The ‘Caption’ is a copy once again (can you tell me what that is, I have Googled it and still don’t get how it applies to an image.)
5.) Descriptions are ‘SIMILAR’, but not exact. Some words are repeated, but with the products being so simialar…
6.) Gallery is setup as ‘Posts’ and using the image as a ‘Featured Image’ without adding it to the post itself (redundant of course).
7.) Most ‘Posts’ have no text, however some have a small explanation of the image. (should I just add text anyway?
8.) The ‘Posts’ do however all have keywords. But they are all of different versions of similar products (image#1 – shoe-blue.jpg, image#2 – shoe-red.jpg and on to 150 images and videos).

**Note: Comments are turned off in the Gallery (however I will blog with comments elsewhere)

My questions are as follows – Related to WP and duplication of information:

If I duplicate ‘Keywords’ (as I suppose that you can since the cloud is based on how many ‘Keywords’ are used and the more the bigger the text when selecting what ‘keywords’). Will there be a penalty at some point with the Search Engines?

Will this duplication in the image tags and post tags being duplicated cause me trouble (as far as the way I have described)?

Can you folks “in the know” look at my structure as described and see where I may run into trouble?

Thanks in advance for any comments and please feel free to comment in my errors and small victories…