Where to put the weight?

Load it up and then Google "CAT Scales".

Take it to the nearest one and the operator will show you how to set up to get a useful set of weights.

Too light of a pin weight causes chucking

You list pin weight of 1410# which is probably mfg. dry pin weight numbers and not your true actual pin weight

You have a 10,000# GVWR trailer so pin weight should be up around 2000#

If you are experiencing chucking load that rig up.
Put the items where you would typically place things...clothes in closet, dishes in kitchen cabinets, toiletries in bathroom, food in fridge/cupboards etc.
Don't over think it.

And carrying water........carry some.
We always have 1/3 fresh water tank on board. Never know when you will need water (place your going to doesn't due to problems etc.) and it's nice to have for those potty breaks.
The weight of that water is NOT going to affect your tow mileage. It is what it is when towing a 'wind sail' down the road.

After you have it all loaded up camp ready (truck & 5vr) go get your actual weights at a weigh station....$12 and worth it!

Pretty much depends on your unit. Needless to say our toyhauler rides better with a load than without. However we had a 34' Big Sky that also rode better when we had the SmartTrailer and motorcycles hooked up to it.

Weight behind the trailer axles can lend to the see saw effect. I like to keep as much as we can forward. Physics 101

15 to 20 percent of trailer total should be on the pin so if you are adding substantial weight, in front of the axles is preferred, of course don't exceed truck capacity.

I think being "balanced" depends on a lot of stuff: in our case, our freshwater tank is in the rear, and the kitchen is in the middle, so I've been keeping the heavier stuff forward of the wheels in the 5er (and not carrying a lot of water)