I play both as well. I have a preference for tyrant at the moment.
On elements, I've upped 833 cards and collected 14 nymphs. That's somewhere around 2/3 of the way through upgrades, that's taken me a couple of years of on-and-off again upgrading, pretty much since the game started.
On tyrants I'm lvl 47 and am missing 3 standard and 3 enclave cards, and have finished all missions, achievements and raids other than oluth. I plan to join a guild soon when I find an appropriate one for me.
Generally speaking I find elements to be less fun, and more of a grind. The bugs (desyncs, game play bugs, cheating etc) directly interfere with my enjoyment of the game in elements, and I miss the total lack of a social element (something the forum tries to provide and mostly fails). I also miss the complete lack of point to progress in elements. What benefit is there to upping cards? There basically is none. I've upped 833 cards, I use about 35, which I swap around about once a month out of boredom, not because of any actual reason. In tyrants, gaining access to cards revolves around collective endeavors in pve (raids) and pvp (guild/faction growth through wars), in turn, your card stock aids you in doing those activities. It's not great, but it's more than elements has. Grinding in tyrants means 2 weeks of mostly waiting for timers to expire. Grinding on elements means 2 years of the same fg battles using the same deck, or not far removed from that. The energy system in tyrants is a good thing as well, as it limits the value of botting and renders it a more casual type of game than it would otherwise be.
At the end of the day, I enjoy playing tyrants, and look forward to expansions coming out, which means more missions, more raids, more card concepts and new challenges. The additional grinding is a minor part of expansions. That's mostly not the case in elements, where expansions just mean more grinding, and I don't think anyone looks forward to grinding fg's for electrum. Taking the last version upgrade in elements, it had the bonus of upgrading the AI difficulty, which had the effect of making grinding marginally harder. Awesome. I know I should've been pleased at better ai and having to alter my grinding deck, but you know, I just wasn't.
The paying player thing in tyrants is disappointing, but it's not that big of a deal for the most part. I've played games that had it worse in that respect. It doesn't really affect pve, and pvp is mostly on a guild basis, so it's not essential for every single member to pay for a guild to compete. I've gained elite (ie, access to the store) and used 145 warbonds without spending a dime, so even as a free player, you do have minor access to the same stuff, just not in bulk.
Anyway, for what it's worth I rated both games the same. The games are what they are, and both are mediocre specimens of their breed.
