help finish this character

[relytdan]

it is an intellect build and would make use of sneak attack and boosting the DC for death attack as high as possible
Rogue 4/ Swordsage 1/ Assassin 8/ Teflammar Shadowlord 6
Rogue ACF: Penetrating Strike
some spells: Deathsight, Dimension Door, Blade of Pain and Fear
items:
Viperfang (City of Splendors Waterdeep 148)
Bracers of Murder (DoTU 98)

so the question is this : Is a race/template with +1 LA the best idea of fill in the last level with OR use a class/prc that bennifits the character and if it goes that route then what +0 LA race is the best idea?

[Vizzerdrix]

I'd say template. If I'm remembering correctly you can get a couple very handy stealth based +1LA templates. (Dark or shadow. I don't quite remember)

[Xervous]

Dark template is the +1 version that grants (ex) Hide in Plain Sight. It is also available from a collar of umbral metamorphosis as a 10min/day or continuous, but of course then it won't function in the evil AMF.
Location: Tome of Magic

Shadow template is a +2 and gives you (Su) Shadow Blend which is a standard action unlimited duration total concealment that only ends forcibly if you're brought into an area of daylight (natural or magical). It also has a bunch of cute little things tacked on.
Location: Lords of Madness

[relytdan]

Dark template is the +1 version that grants (ex) Hide in Plain Sight. It is also available from a collar of umbral metamorphosis as a 10min/day or continuous, but of course then it won't function in the evil AMF.
Location: Tome of Magic

Shadow template is a +2 and gives you (Su) Shadow Blend which is a standard action unlimited duration total concealment that only ends forcibly if you're brought into an area of daylight (natural or magical). It also has a bunch of cute little things tacked on.
Location: Lords of Madness

well while decent choices - don't really need dark for HIPS as assassin will get that and not to keen on shadow either

any other ideas?