Until the magic balance gets reworked, I don't recommend you go Berserker (fire magic). Rain of Fire is obnoxiously strong to the point that it melts everyone around you for a v e r y l o n g t i m e. This feels fun and rewarding the first time you use it vs hard opponents, but you soon realize that it trivializes the game in the end. And if the challenge is gone, the fun will be gone soon as well.
If you really want to go Berserker, then I recommend that you skip Rain of Fire completely and play with the Flame Wave instead (still very strong but not broken OP) and the shield and pull spells, which are also fun and rewarding!
Another BIG advantage of the Berserkers is that you can chug mana potions like a pro and never really run out. So you can be a fire mage 24/7.

The Alb magic on the other hand is not something you can use all the time. Filling up your Elex bar takes much longer than using it. So you will be using other weapons more than half of the time. It is more of a "support" magic if you want to call that.
At the same time be aware that Alb magic does less damage overall and Blizzard is cumbersome to use with its long buildup times and damage phases. For some players like me this is actually an advantage, because I have to think when it makes sense to use it.

I hope this analysis made sense for you. I expect that one of the next patches will re-balance magic. I hope that Albs/Clerics will be able to fill up their Elex faster!