These are some major coins that fall under these categories which can be big in future and has an appealing concept and a good team
Speed and scalability: High Performance Blockchain, Trinity, Cardano
Ecosystems: Wanchain, ICON, CargoX
Standardization: Appcoins, Publica
Fee-less: IOTA, INT Chain, Raiblocks (Nano)
Decentralized Exchanges: Cobinhood
Disruptors: Power Ledger, BitDegree, Ethos, WePower