Tutorial guides will familiarize you with the decks, making it easy for beginner players to have fun
Some color combinations simply dont have any mana ramp worth playing at all, either forcing you to consider extremely mediocre options or exclusively rely on single color cards and mana rocks to get the job done: Dimir (Blue/Black) Boros (Red/White) Orzhov (Black/White) Esper (Black/Blue/White) Grixis (Blue/Black/Red) Abzan (Green/Black/White) Sultai (Black/Green/Blue) Temur (Green/Blue/Red) Most 4-color groupings That doesnt mean all other color combinations have amazing ramp options though many can only offer situationally powerful cards
As for its value, Red Supernova Dragon was worth $185 at the launch of Battle of Legend: Glorious Gallery, but has grown slightly to just over the $190 mark
Then they didn't, and now they do again
I think this card is neat, and its cool seeing a Kiki-Jiki effect on a 3/3 for four mana in Standard
When it comes to building your deck you want it to work as a toolbox to deal with threats while also having threats of your own later down the chain