I've only used 71B for meads. About 1.145-1.150 is a good target for OG for a sweet mead. Should finish around 1.020-1.030 range with proper fermentation (staggered nutrients, degassing, cap management, temp control, etc.).
I did a strawberry mead similar to what you're describing last year. Two pounds/gal of strawberries in primary and again in secondary, plus 4oz of blackcurrants in primary for a little tannin. The strawberry is underwhelming, even at 4lb/gallon. The only thing I haven't done yet is add some acid blend. I'm hoping that may amp up the strawberry a bit.