The one thing you should do is remove the extra log files. There is no benefit from multiple log files, SQL uses them in sequence.
Second, how many files depends on whether you're seeing allocation contention in TempDB. If you are, try going to 8 files. If you're not, leave it at 4.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability