There are a few viewing windows in the hood, none of which is, however, a full-featured one, so to speak. After extending the canopy, you'll get two ventilation windows on the top sides which also serve as peekaboo windows. There is also the option of rear ventilation on the reclined rear part when the child is napping, so through there (after opening the flap in the back), air can also circulate through and you can also see the child if you bend down.
The EVA foam-covered wheels are the most lightweight but also the most basic ones. They are certainly less durable than rubber wheels but for such an ultracompact buggy, their low weight and maneuverability suit well enough. Read more about wheels and their different types (+comparison) in this stroller wheels article.
To your last question, you picked reasonably well, this is a nice, quality travel stroller that folds down by itself, so great for one-hand folding. The 22 kg weight capacity here is, however, a bit overrated, as the seat is not as large as to accommodate a 22 kg, approx. 5 years old child. I have one such at home and he doesn't fit. It is pretty much true for all of these compact travel buggies - however, if you absolutely need something for that bug of a toddler, go for a taller seatback and more space up to the top of the canopy (the Ergobaby Metro+ is a bot longer, seat surface-wise, but I would consider a Joolz Aer more in terms of seatback height). Then there's also the Chicco Goody (full Chicco Goody/Goody+ review here which is spacious enough, but without the peek-a-boo window you needed.
Still, even the Jackey will be OK if not asking it to last for a 5yo. For a 1-to-3 years old, I can recommend this one just fine. If a larger toddler is on your mind and shoulders, however, do consider taller backrests or mid-size strollers instead - I mean, you can always take it on board as the baby's free luggage. Last thing - if your stroller priority is the small size with the larger toddler in mind and you're only considering the Jackey vs. the Metro, I personally would go with the Metro, I think. The Metro is also a bit smaller after folding. However, for ride comfort, the Jackey might be a little better off.