The best that came to me was the Cybex Mios which is fantastically ventilated, sturdy and compact, and offers a bassinet option as well. I personally loved that stroller and it is comfortable despite the smaller wheels and compact dimensions. I am, however, not sure about the price which will most probably be higher, especially as a 4in1 set (I saw a nice price for a 4in1 set in the UK for about 930 GBP, so a bit more for sure). A pre-owned one would also work, of course, though that choice is up to you.
Apart from that, you might want to consider something simpler, just forward facing, like a Joolz Aer with a cot. I am, however, not sure if that is the best option for an only stroller, I personally would want something that was not meant as a travel = occasional use stroller.
Lastly, I'll mention the Valco baby brand which is simple, light, and with multiple options that usually take on a carrycot. Try think about the options I mentioned, and let me know about more requirement OR what you'd be able to compromise in to get to the right stroller (or amount of money).