We did this trip on Oceania (same ships) it was great .
Depends on your personal preferences but we prefer the smaller ships.
we went in January & it was hot.
We did a tour in Costa Rica with "Okey dokey tours"
Not sure what ports of call AZA does.
If you stop in Acapulco book a private tour with Rosy she is the best
Alexandr Pushkin, Carnival-Holiday, HAL-(old)Westerdam, Orient lines-Marco Polo, Royal Olympic-Olympic, NCL-Dream, Dawn-Princess, ACCL-Grande Caribe, Oceania-Insignia (3), Regatta(4) Marina (1) St Lawrence Cruise Lines-Canadian Empress
Scenic River cruise June 11,2012