Hola Caz, and welcome to the forum! Sorry to hear about Lanzarote Beach Club - there were a number of people left high and dry there weren't there? I heard there's a court case going on - but I don't really know much about it.
In Playa Blanca, there's now a bowling club that your 14 year old might enjoy. Hubby's 3 boys loved it there, and it doesn't break the bank either.
www.bowlingclub-lanzarote.co.uk It's in the new Marina Rubicon Shopping Centre, so ideal for the end of PB you're staying in.
Also, maybe have a look at Kikoland which is in the grounds of the Princess Yaiza hotel. There's all sorts of sporty stuff happening to keep your man and nipper occupied.
You mentioned Rancho Texas. We haven't been yet, but have heard it's good there. I think you can get a coach from Playa Blanca in the evenings for their Wild West Show too. If you like the animal theme, then give Guinate a try.
www.guinatepark.com It's up in the North of the Island, and we love it there. We thought it was just about birds and flowers before we actually went, but they've also got some other animals there now too. I had my hand held by an otter (which I was very excited about). They've also just taken delivery of some Rumboldt penguins, who are settling in really well. If you and the family like your scenery... then as you come out of the Guinate car park, turn right instead of left... and go to the end of the road. the views across to Graciosa are spectacular, and we think they're better than the Mirador del Rio views (and it's free too). We get there by going to Uga, then heading through La Geria, then past Famara (a fantastic beach), and Teguise (Sunday markets), and following the signs to Haria. the mountain road views are fantastic, and you'd miss out on that if you took the coast road. Once you get into Haria village, you'll see signs for Guinate Park.
You could also get the ferry over to Corralejo from Playa Blanca, and hit the water park. It's far better than the one in Lanzarote.
As for sea trips... go and see Tracey at Snorkelling Delights. You can find her shop in the Burger King complex by Playa Dorada. She organises everything from boat trips, to snorkelling.
Have fun!
Flooey xx