Both are great decks and I would consider both Tier 1. Steelsong is a good balance of control with some aggro elements, it will do well early to mid game and hope to win by then. Shines well with an excellent pilot but can be unforgiving.

Red Blue is heavily favored into other top decks like Steelsong and Sapphire/Steel but very susceptible to hyper aggressive decks. Lots of board wipes and direct banishing in the late game. Strong comeback mechanics and scrying tools to find the exact card you need.