There are more exotic, remote areas of Costa Rica to visit, it's true. These come with their own benefits and certainly challenges in achieving your vacation goals. I didn't see any sloths when I visited the Guanacaste region of Costa Rica in 2015, for example.
However, it does have a rapidly growing tourism infrastructure, possibly a little more welcoming than other areas of Costa Rica. There are also opportunities to learn to surf and some great beaches, alongside the waterfalls and wildlife you might expect.
The developed tourism aspect really helped keep life on vacation a simple one. We didn't have to work hard to find activities or to discover a great place to eat.
Costa Rica still kept it wild though, with plenty of activities such as hiking a volcano to then enjoy a volcanic mud bath or scuba diving to see bull sharks. More than enough to keep everyone and their varied interests satisfied throughout the day. Keeping busy at play all day then retiring to some place comfortable to joke around and relax - which is what we all wanted in a big family group trip.
Highlights for me were the sound of howler monkeys each morning and cards by the pool in the late afternoon when the day's fun had been enjoyed.