We've decided to have a big holiday

What's the budget roughly?

Do you get that time off normally or is it a one-off.

If its a large budget I would go round South America or Australia, loads of animals in both. Smaller I would be sticking to Europe or going for a shorter time. Costa Rica was amazing for animals. Far North Queensland has loads of animals, tree kangaroos, possums, rock wallabies, cassowaries, platypus, koalas etc. Within Europe there's bears in Finland and Sweden, dolphins around Azores you can swim with in ocean. Costa Rica needs hep A vaccine.

id love to camp around europe, but it depends how long you want to stay in each place, maybe a large tent for longer stays and using basic pop up tents for 1-2 nights

Se Asia weather is not great in July and august - dry areas include Bali, Java, Borneo, parts of Thailand and parts of Vietnam.
Personally the USA trip sounds good or Canada.

I guess you need to decide what kind of thing you want to do to start with. You could drive over to France and head in any direction, taking your tent or stopping wherever. Or you could fly to Helsinki and train and bus it all the way to Lisbon. Or anything in between!

I put together an itinerary for a client driving across Italy (I’m a travel agent) and they did an open jaw flight between the start and end point then a combination of Eurocamp and self catering places. Also did car hire from airport to airport which is a bit extra but worked well for them.
They were away for about 4 weeks do got to see a lot of Italy but you could easily make it across a few countries in your timeframe. I’ve always fancied doing the ferry from Italy to Croatia

We spent 18 months travelling with 3 kids age 2 to 8. Europe australasia and USA. We mainly airbnb-ed and tied to get central locations. Rented vehicles in the states but mainly tries to walk from where we were staying or take public transport. Fly or train to each location.

It all depends what you want to see/do, though. 3 months in France on a bicycle? 15 countries in 2 months? Budget? Self catering or trying a new culture's food? One backpack for 4 or a suitcase each ....

I would do USA - the national parks. You would see amazing sights - Yellowstone, huge dinosaur skeletons, so much wildlife and natural beauty. You could hire an RV (might be pricey - don't know) and take your time....

SE Asia would be the way to go! It’s very cheap and adventurous

Can you try an independent travel agent? We’re not in UK but there’s loads of ‘travel counsellors’ where we are who can plan things like that - we’ve just used one for a trip around Italy and lots of friends use them for Europe trips over summer