im no expert but this is gona be my PvP build when i respec, ignore the levels i slot things, been changing it loads.
Exported from version 1.5C of CoH Planner
http://joechott.com/coh
Archetype: Scrapper
Primary Powers - Ranged : Katana
Secondary Powers - Support : Regeneration
01 : Fast Healing hel(01) hel(3) hel(3)
01 : Sting of the Wasp dam(01) dam(9) dam(9) acc(42) acc(43) endred(43)
02 : Flashing Steel dam(02) dam(19) dam(43) acc(46) acc(48) endred(50)
04 : Quick Recovery endrec(04) endrec(5) endrec(5)
06 : Build Up recred(06) recred(7) recred(7)
08 : Reconstruction hel(08) hel(31) hel(31) recred(31) recred(13) recred(40)
10 : Dull Pain hel(10) hel(11) hel(11) recred(15) recred(15) recred(13)
12 : Combat Jumping defbuf(12)
14 : Super Jump endred(14)
16 : Integration hel(16) hel(17) hel(17) endred(19)
18 : The Lotus Drops dam(18) dam(21) dam(21) acc(45) acc(25) endred(25)
20 : Hasten recred(20) recred(23) recred(23)
22 : Resilience damres(22) damres(46)
24 : Kick (Fight) acc(24)
26 : Soaring Dragon dam(26) dam(27) dam(27) acc(34) acc(42) endred(42)
28 : Instant Healing hel(28) hel(29) hel(29) recred(36) recred(36) recred(36)
30 : Swift runspd(30)
32 : Golden Dragonfly dam(32) dam(33) dam(33) acc(33) endred(34) recred(34)
35 : Tough damres(35) damres(37) damres(37) endred(37)
38 : Moment of Glory damres(38) damres(39) damres(39) defbuf(39) defbuf(40) defbuf(40)
41 : Focused Accuracy endred(41) thtbuf(46)
44 : Conserve Power recred(44) recred(45) recred(45)
47 : Health hel(47) hel(48) hel(48)
49 : Stamina endrec(49) endrec(50) endrec(50)
-------------------------------------------
01 : Brawl Empty(01)
01 : Sprint Empty(01)
02 : Rest Empty(02)
No Divine Avalanche 
Would be an idea getting Hasten to get DP back and have it on for double the duration. Only a 15 second down time when using the two powers together. Not to mention it speeds up you Reconstruction too.
Anoyne out there who can knock up a decent lvl 50 katana/regen build for PvP?
Would do it myself but not played my scrapper since ED and don't have a clue how to respec him