I have a Wild Country Zephyros 2. Excellent and very light
Yep this would be one of my choices if i didn't already have a Vaude Taurus Ultralight 1.9kg which has been pretty good.
But also the MSR Hubba Hubba of similar weight around the 1.7 to 1.9 kg mark is a favourite of many RTW touring cyclists.
The Nordisk Telemark 2 man weighs in at 950g and is a 3 season tent. Feels like parachute material. Has DAC poles as well. Very easy and quick to pitch.
I would avoid Easycamp tents. They are aimed at summer holiday or festival goers. They are not particularly durable or light and have fibreglass poles much like most cheap nasty tents. Fibreglass poles break so easily and are heavy.
The point of a footprint or aftermarket groundsheet is it adds a layer of protection to a thin tent groundsheet. If you don't have one you risk having the tent groundsheet puncture and if it rains heavily or you camped in a river bed then all your stuff could get wet. A wet sleeping bag and clothing is curtains. You could use a bivi bag inside your tent I s'pose. When riding I store the aftermarket groundsheet down the back of one of the rear panniers. It hardly takes up any space at all.
Re water treatment. Iodine now banned. It is Chlorine tabs to clean up water. To counteract the chlorine taste neutralising tabs are available. For more dodgy water chlorine dioxide tablets are better. You can also get various water purifiers some more expensive than others. Sawyer make an in line filter which is good for 10k litres which can be used in line of tubing of a hydration bladder such as a Camelbak or on top of a water bottle. There are various Steripens which use UV to kill nasties. There are also Katadyn range of filters which are a little more expensive around the £120 mark. You can get water bottles which have a carbon filter in the screw cap which takes a lot of nasties out. Or as already said you can boil water but which takes time and fuel plus it has to cool before you can drink it. Why not just drink Coke and Vodka instead?
Personally I would always filter water from streams as others have said above as you don't know if there is a dead animal in the water up stream or a whole herd of wildebeest has shat and pissed in the water. Which begs the question why don't animals get ill drinking from watering holes which are no doubt harbouring all sorts of nasties?
HTH.