The good news is none of those are tender ports (at least I think Solstice class ships should be able to dock there). Sorry I can't provide much help beyond that. Unfortunately we don't give accessibility much attendtion until we are faced with it. Roseau might be your most challenging part dock is right at the street and the town isn't particularly flat.
A Bad Day At Sea [with power] Always Beats A Good Day At Work
Alaska 2014 - haven't picked a cruise yet
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012
Celebrity: Summit 2011
Princess: Ruby 2010, Caribbean 2013