We obviously know they're both Red rangers/heroes and the fact that they've made excellent leaders for both their teams. However, Sean did mention the fact of the newer Sentai leaders having nostalgic backgrounds to the first Power Rangers leaders. I thought I can point out a few. I chose Takeru since he's the one I know best.
Takeru was considered one of the best Red heroes of the 00's era. Whereas Jason was considered the best Red Ranger of all time. What could possibly give them these titles? Jason, obviously, had often been the most serious during battle with Rita's monsters. Of course we know he was a fun guy outside being a ranger, but the same went with Takeru. Takeru is perhaps the most serious of all the red rangers in the past many Sentai series'. From what I recall, he had only been caught laughting or smiling whenever Genta (ShinkenGold) did something hilarious. And that didn't happen too often.
Furthermore, Jason was the most passionate about dealing with Rita. Takeru was the same, but he was more on the side of protecting himself rather than defeating the Ayakashi. The rangers/heroes were more loyal to their leaders, Jason and Takeru, more than most other series' had displayed in their respective shows.