Personally, I play Max line and if there is a Power play option, I will also go for it.
Max Line is to catch as many full house as possible. This is because the Paytable for full house vs 3 or 4 column win is vastly different. For eg, for 5D, the 5 phoenix pays 1000, and 4 phoenix pays 100 and 3 phoenix pays 50. So if I play 5 lines/10 lines/15 lines vs 25 lines on 1 credit per line, I can save from 10-20 credits per bet. But potentially, I can miss the full house which pays 1000 and only get 100 or 50 credits payout. i.e. the opportunity cost is between 900-950 credits. I am quite bothered by the opportunity loss and hence I will always play max line and 90% of the time, I will pay additional for the Power Play.
All said, I agree with Bro Kia that if stretching BR is priority, then it would better to play less lines.
Max Line is to catch as many full house as possible. This is because the Paytable for full house vs 3 or 4 column win is vastly different. For eg, for 5D, the 5 phoenix pays 1000, and 4 phoenix pays 100 and 3 phoenix pays 50. So if I play 5 lines/10 lines/15 lines vs 25 lines on 1 credit per line, I can save from 10-20 credits per bet. But potentially, I can miss the full house which pays 1000 and only get 100 or 50 credits payout. i.e. the opportunity cost is between 900-950 credits. I am quite bothered by the opportunity loss and hence I will always play max line and 90% of the time, I will pay additional for the Power Play.
All said, I agree with Bro Kia that if stretching BR is priority, then it would better to play less lines.