I guess the term "near to the park and beaches" is sort of relative. Pretty much anywhere in the Quepos /Manue Antonio area is within 10 minutes from the beach by car. But if you want to walk on a regular basis - that is a bit different. Much of the area is not that conducive to walking. Most of the places within walking distance have already been mentioned.
Plaza Yara sound good - but it is not walking distance. it is actually closer to Quepos than MA.
And to be fair to places like Inn on the Park (I have no experience with it except walking by) yes it has a few negative reviews - but it has more positive than negative. If you look at any property you will find some people who did not like it.
If you are prepared to look for places that are not really walking distance, you could look at Villas Nicolas, Villas Mymosa, , casitas Eclipse. Or depending on the number in your party, the length of your stay and your budget, there are plenty of houses, condos and villas to look at that have kitchen facilities.
raquel