This stroller doesn't recline fully, but the recline is rather deep. Personally, I would use it from about 6 months IF you mean to use the seat only, and not with a car seat. But with a larger 4-5mo that is already strong, it perhaps could be used. However, with such a size and small wheels, I would not really recommend this for an everyday stroler, none of the strollers of this size were meant for that, they are more occasional strollers for the mall, traveling, to the grandparents, and so on. Definitely not for regular terrain or very bad pavements.
The folded dimensions of 56 cm x 45 cm x 25 cm should fit the cabin size requirements for most airlines, but you always have to check yours, especially the budget-ones have stricter rules. It always differs from airline to airline.
The seat is actually wide enough and wider than some other travel strollers. It is comfy enough, however, with no adjustable leg rest, not all children like to nap in it. The canopy also isn't the longest, especially when reclined.
The handle is at about 102 cm, which is not too high. For a 170cm person, it should be ok enough, but I'm afraid your 180cm husband may already find the handlebar height uncomfortable.