I'd say, odd are, that if you're just interested in throughput, the standard Hotspot GC without any options isn't going to give you optimal performance. I've found that, like gtani, mentions you'll have to spend time tuning to get the performance you want.
In a similar situation, I found that the Parallel Old was, by far, the fastest (throughput) collector.
I'd say low fruit are -server, Xmx, Xms and MaxInlineSize and looking for boxing/unboxing. At the other extreme, is it worth it to your company to spend a few weeks reading the Hunt/John book and benchmarking thoroughly?
In a similar situation, I found that the Parallel Old was, by far, the fastest (throughput) collector.