Kino's

[Trig]

Where did they go, or what were they replaced with?

Pretty sure we havent seen anything like them before Destiny, why not?

[General Jumper One]

Because they probably were forgotten and they had puddle jumpers with super sensors

[Quetzocoetl]

Yeah, once you build a spaceship with built in life support, weapons and invisibility, you can just go from planet to planet without peering through the gate first.

[sgc]

The Ancients didn't need MALP's because they built the Stargates. They knew what was where and on which planet, or the newer (<50 million years) gates may have sensors built in them that are only usable by the Ancients. The Destiny gates wouldn't have those sensors, and they needed the Kinos to retrieve atmospheric readings.