Montezuma is a nice town, two main streets have everything you need, which is 1 block off the beach. The main road leading south has more lodging and cafes, via foot or ride a bike.
Playa Cahuita nearby has a the Sloth Sanctuary to, just north.
Playa Nosora is two towns, one on the ocean is a few hotels/lodging, surf camp and the main town is inland about 2KM up a road, there you have all the needs from ATM, Grocer, cafes. shops, airport, school etc.
Playa Samara is a town similar in size to Montezuma, with lodging on the ocean and also 1 block inland is a city block with all lodging, cafes, bars and car/atms etc...it is more a traditional town in the main center has a soccer field and a church at one end, where as Montezuma and Nosora are spread out more rectangle in shape than square.
Playa Cahuita is also 4 streets of homes, shops and cafes/bars, a few on the near the ocean, but the main drag is the bars/music etc. The park is at south end.
All the towns mentioned above a bike is all you need, or a 15 min walk pretty much covers your needs.
There pics I have taken of the various towns Here