tumblr is shit. not da shit. just “shit”.
IME you’ll also need more HTML/CSS knowledge if you want to style tumblr cf. WordPress and it’s mainly full of skinny angst ridden teens reblogging sub /b/ shite. Oh, and occasionally you will be taken down in the DDOS wars between the aforesaid /b/tards and tumblr
Stick with WordPress – it’s a widely used CMS so WordPress skills may help on your CV. I would imagine most of what you want to do regarding images can be achieved by defining some CSS classes. For instance classes for centred or “hanging caps” positions, whether they are photos or not so have borders or not… and so on
Blogspot is also good though I found it less flexible than WordPress. Haven’t use it since 2005 so it may have got better.
Typepad http://www.typepad.com is another choice but I have no experience on which to recommend or otherwise. Drupal http://www.drupal.org is another popular CMS.
Oh – if you’re uploading images, try the NextGEN Gallery plugin, http://alexrabe.de/wordpress-plugins/nextgen-gallery/. Allows you to upload a bunch of images in a single zip archive. Made my life a whole lot easier than managing an integrated WordPress/Gallery2 site.