What do people think , for card accumulation is constructed better than arena, or vice versa?
Depends. If you can consistently win 3 games then it is worth. It also depends on what cards you need, since Arena only gives GvG packs as rewards (you can still get individual Classic cards as rewards).
Warlock is pretty bad in Arena, but it has gotten a bit better. Mage and Paladin are the top two classes, because their best Arena cards are basic or common rarity, so there's more chance for them to come up. Only your 1st, 10th, 20th and 30th cards are guaranteed to be rare or better. Mages also have Flamestrike, which enables them to come from behind and win games they have no business winning.
Also, definitely use a tier list like HearthArena, but follow this:
First 10 cards: Quality over curve (pick the card with the highest rating)
Second 10 cards: Curve over quality (you want 6-8 2-drops for instance, and the 4-drop slot is crucial as well. In GvG Arena, miss an early drop and you probably lose)
Last 10 cards: Fill gaps in your deck (removal, AoE, Taunts, heals, maybe even an extra win condition etc)
Don't just click play the minute the gold swoosh comes down. Study your deck. How are you going to win? What is your best opener? How are you going to deal with Mages?
If you can play the game to a decent standard, it is probably drafting that is holding you back. I couldn't win an arena game for love nor money, but consulting the tier list has meant I can get 4-6 wins fairly often now.
I'm currently 4-0 with a Priest deck that really shouldn't be winning games. I have too much late game (2 Sea Giants, 2 Enforcers, 2 Cabal and a Mind Control) but I've been doing well.
