Hi and

I seem to be one of the few here that owned a 6 inch dob (until recently), so I'll speak from my own experience. Yes! It is a good choice and you will see plenty! The Moon, planets (the rings of Saturn & the belts on Jupiter and their moons for example), nebulas, galaxies (albeit, feint smudges), globular clusters, the whole deal! The 6" is considered to be the entry level "serious scope" for deep sky observing - you won't be disappointed.
It's size and portability is fantastic for what it can do. To make mine more portable, I put wheels on the base and pulled it along by the tension handle, and If I needed to pick it up, it was do-able. If you plan on transporting the scope in your car, it is a good idea to make sure that it fits. I have a large family car and the tube just fits in the boot and the base takes up half the back seat (too big for the boot). I see you have two children and yourself, so that's three in the car so far with the base, so you see my point? Otherwise, there's nothing wrong with backyard observing, that's what many people do, myself included - and I see plenty to keep me happy.
Not that you asked the following questions but I'll note them anyway... Regarding collimation of the mirror, the stores are very helpful with showing people how to do it (you will need to learn this). As for the eyepieces, you will find the 25mm eyepiece is the one you will use the most, and the 10mm (higher mag). mainly on planets.
Skywatcher & Saxon are produced from the same factory, I've been told by several different stores and people that they're exactly the same, just re-badged. I have owned two Saxon dobs (formerly the 6" and currently the 10") and I am very happy with them.
Until Christimas arrives, have you thought about getting them started on learning the constellations to get a head start? A planisphere (around $15) can be purchased from most telescope shops (on-line from Andrews, Bintel etc) and is terrific in helping beginners learn the skies (especially as they change shape during the night- can get a bit confusing). Both my Saxon dobs came free with "Starry Night" software which has been highly invaluable in helping me. I print the maps out as I need them, scribble notes of what the objects are that I've highlighted on the map, put them in plastic sleeves in a folder and off I go. I've ended up keeping the maps as they have served to be great log diaries with my notes on them. I use a 2-ring binder which balances well on my lap.
Your children (and yourself!) are going to be in for such as great treat when you get your telescope! Enjoy!
Kind regards,
Suzy.
P.S. Know this in advance- when you buy your scope, it will rain that day and maybe even for the rest of the week. It happens, it just does

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