WordPress Blog, re-design + switching to a new theme

Hello there, so a while back I have created my first blog in WordPress.. and when I look at it right now it kinda makes me sick because I have learned so much in aspects of design, WordPress, SEO and other stuff that I want to fix it, give it a new look, and make it more functional and faster. The only question that I have that it contains a lot of posts, (46) with pictures that are really slowing down the site, and the posts are not seo friendly same goes to titlles. So should I do put in a new template, use some kind of a gallery plugin so it shows smaller pictures and then re-do everything manually?<br>http://myshelterandi.com - thats the blog, what you think?