These are all excellent recommendations. I would also recommend Deadly Combat, as it is quite fun and challenging improvement to the vanilla combat. Just make sure you opt for the no weapon range change, or you might end up with strange AI behaviors. Deadly dragons is also a big improvement over vanilla puff the magic dragon AI. Duke Patrick is extremely awesome, and is in my current rotation.
I have enjoyed using http://skyrim.nexusmods.com/downloads/file.php?id=1269 (Better AI, more spawns) in conjunction with http://tesalliance.org/forums/index.php?/files/file/1139-duke-patricks-heavy-weapons-combat/ (More enjoyable combat, only activate the esp after you have left Helgen). I would also recommend using http://skyrim.nexusmods.com/downloads/file.php?id=1002, though you might need to make a bashed patch for the balance and distribution part to work withe PISE. You might also consider http://skyrim.nexusmods.com/downloads/file.php?id=2933 which overhauls the smithing (can't improve things as much, need to use gem dust to improve weapons) and allows you to make a version of any sword in any metal (like a steel dwemer sword or ebony nordic sword) though you will have to make a bashed patch to make sure it works well with the other mods.