So my first playthrough I was sentinal and really enjoyed.  Now from what I have heard Insanity is a bitch to do but I wanna 100% the game so my question is can I start a new game and import my character and still get the trophy
 
A simple yes or no would work. Thanks!

Yeah, though it's apparently not advised since the enemies still scale with your level, thus making it more difficult. I done my Insanity run with a Sentinel too, straight from scratch (well, imported from ME1 still) and found it fairly challenging but still attainable.

make a fresh solider with warp ammo its so easy

Do a new game for sure, the enemies will be weaker early on, and you can use the upgrade system to keep an edge on them. That's how I did it. Soldier will make it the easiest ride, with the slow down power and sniper rifle you will handle most situations with ease.

Yeah, I did a fresh Soldier run as well. Most of it was cake as long as you have at least one member with warp and another to take down shields.

Im doing a Insanity Adept run.... its fucking ridiculously hard in some spots. 

• Tali for the vents.
• Garrus/Jacob lead the secondary teams.
• Jack/Samara for the biotic bubble.
• Anyone, really, for escorting your crew back. (which btw also requires you do save all the crew members along with your entire party surviving)

If you just want the trophy for insane, skip all the loyalty quests (and side quests in general) since they will just increase your level and make the quests harder. Only do quests that you need for story or that give you can upgrade (Mass Effect Wiki can show you which ones).  
 
If you want the whole team to survive, I recommend just reloading a save before the collectors ship on casual and make sure you have done the following: All loyalty missions, all ship upgrades and choose the right leaders for each mission (i.e don't chose Jacob to hack, or Legion to lead the second team,etc).

" @Abyssfull:  I seriously did all of that but for some reason I still lost somebody.  Im thinkin not doing any side missions cept for loyalty should help though "

 http://www.giantbomb.com/guides/suicide-mission-guide/1551/

I remember that I tried to play insanity right after I finished the game on normal, I imported my vanguard and it was almost impossible to get past the first level.

" @Sackmanjones:  
Long as you have everyone Loyal, and you choose the right party members for the right objectives, it should nail down the achievement with ease. Which party members to go with what objectives is obvious enough, but just in case, the most sure bet is to have:  
 

• Tali for the vents.
• Garrus/Jacob lead the secondary teams.
• Jack/Samara for the biotic bubble.
• Anyone, really, for escorting your crew back. (which btw also requires you do save all the crew members along with your entire party surviving)

"

So my first playthrough I was sentinal and really enjoyed.  Now from what I have heard Insanity is a bitch to do but I wanna 100% the game so my question is can I start a new game and import my character and still get the trophy  A simple yes or no would work. Thanks!

While the Kasumi DLC is a bit of a pain early on you get a godlike SMG so its worth getting at early.

While the Kasumi DLC is a bit of a pain early on you get a godlike SMG so its worth getting at early.

Its so good I have preemptively decided to choose sniper rifles as my extra weapon specalization because I don't need assault rifles now.

I love that DLC assault rifle though. It packs a hell of a punch, great against armour. Also makes you feel badass.
Fuck BOOM you BOOM Harbinger BOOM.

Insanity runs can be done (kinda) well with vanguards. If you spec into shield regen when you charge and use the shotgun you get if you have the cerberus network, you can cut off the infinite spawn areas that happen a lot in the game and do crazy damage. And since guns do tons of damage at melee range, charging and then shotgunning guys does crazy damage. Also, if you buy one of the weapon packs, you get an awesome rifle, a pretty good pistol, and a badass geth shotgun that charges up.