This is entirely biased opinion, but having Lance as the champ was the coolest shit back in the day.
>be me, bab anon, playing Gold for the first time
>get to Mahogany Town and meet Lance
>oh shit, it's the guy from Red and Blue
>only other gen 1 character you meet before that point is Oak, so it's awesome seeing one of the strongest trainers from the previous game
>beat TR and move on, thinking of Lance as only a cameo
>later on, on my way to the League, some NPC tells me I just took my first step in Kanto
>mfw
>put two and two together and realize it's the same Pokemon League as in the last game
>hyped as fuck to fight the old e4 again, predict that the rival will end up as the final boss like in the last games
>eventually reach the Indigo Plateau, ready to fight Lorelei
>Elite Four Will wants to battle!
>literallywho.jpg
>as I progress I slowly realize that these aren't the old e4 members at all, sans Bruno
>now I have no idea who the final boss will be
>beat Karen and reach the champion's room
>it's the BAMF who hyper beamed a Rocket grunt
I don't think a single moment in a pokemon game will ever match up to how awestruck I was at stepping foot into Kanto and defeating Lance again back in Gen 2. I've always had Lance as my favorite champ for that reason.