I spend most of my time in PvP (that mostly rewards time spent), and enjoy GvG (that mostly rewards strategy and tactics, RNG aside) at the current 4-week intervals: each game mode rewards different approaches, and provides different challenges.
However, I wouldn’t mind an additional PvP game mode for individual players where points are calculated somewhat like in GvG: a global ranking would allow players who do not necessarily have the time to grind through a whole event/week to be rewarded for their skill.
To help ensure the quality of Attackers/Defenders, there could be a Gem Fee (100?) to register for the event, so only those who are interested would be involved in this game mode: this would also keep the gem economy moving, which I understand is seen favorably by the devs/publisher.
This could even be an ongoing event, with a single daily battle (Mon-Sat bonus points for specific colors, Sunday any color goes or bonus for all troops having unique colors), and the winner could be determined at the end of every 4-week cycle. Rewards could include unique Avatars/Titles/Golden Hero Frames, that may be of interest to players of all walks, even those who are swimming in resources.
Ok, done typing the raw concept I just thought of, feel free to polish or dismiss as appropriate.