Honestly, this game is fun. BUT it does favor one of two extremes either you draw exactly what you want to get you hooked, or you draw 5 lands while your opponent gets all the cards they need. VERY, VERY RARELY is it a decent match. I've played 10 matches today and lost all but 1. Why? For those reasons above. This game also allows people to cheat such as casting a 2 mana spell for 1 mana with no cost reduction.
The shuffling system needs a lot of work. Rarely when I shuffle playing paper do I draw three of the same card; even more unlikely that I'd draw the exact same three cards after shuffling. There have been matches where opponents highlight their hands and back off, pause for a minute until the timer starts and then the "Heart of the Cards" card saves them and they win.There are no ways to report players for suspicion of cheating.
The events that were supposed to be free cost money (in game). The matchmaking system pairs you with people who are 1-3 tiers above you. IF you lose against them you still drop down in your tier. And when you select full control it only works maybe half the time.
Almost after every major sanctioned event Arena gets flooded with the decks from that event. So that is quite annoying if you want to have some fun. It is nice to play in non ranked to see some jank but there are the few who don't know how the event winning deck works playing in unranked is quite a nuisance.
Those are a few of the gripes about this game. The great thing is learning how the triggers work, priority, and other mechanics. It is fun to find the jank decks and see how well they perform. I come back to this game every once in awhile to play around with cards that I think would be fun. I'd play a bit more if they actually fixed a few of those issues that has been plaguing arena since it's inception. I can't imagine it would be too difficult to copy the shuffling system from MTGO.
There has been some articles floating around about Arena workers messing with people and stacking the game against some people. There are some flaws in this game but it's a nice waste of time when you don't want to go out to get your MTG fix.