Travelling to La Palma, Canary Islands to see the stars - advice please!

Hi all! I'm thinking of booking to take my wife and three kids to La Palma this summer to see the stars and do some hiking.

Can anyone recommend the best way of doing some star gazing and any good hikes. Would love to hike to the observatories in the evening and spend a few hours viewing the stars one night. Also the forests to the north look amazing. I've seen there are some star gazing tours available. Are these worth it or is it easy enough to do yourself?

There seem to be a lot of options so I guess hiring a car is a must.

Also, there are a few resorts around the island. Is any of them particularly well placed for access to routes and amenities or is the whole island pretty accessible?

Lastly, it seems only Tui fly from the UK, Thursday to Thursday. Is there any other options for getting there, i.e. flying to Gran Canaria / Tenerife and getting a transfer by boat or plane?

Sorry, lots of questions there but there is both lots of information our there on websites but very few specifics so i'm finding it a little difficult to plan.