Mass Effect 1 or 2? It appears as though you are asking about Mass Effect 1 since you can get Garrus and Tali early. I recommend checking out Simbacca's
[Mass Effect 1] Start of the Journey: Single Playthrough Builds thread. It also includes a link to the ME1 Talent Calculator which should also help.
Note that you cannot get to level 60 on one playthrough without modding (requires at least two playthroughs); highest you can get is level 58 I think. Generally, if you try to get everything you should end up between level 54-58, depending on whether you use the Mako to kill enemies or not. Killing with the Mako earns you less XP than if you kill on foot.
If you are asking about Mass Effect 2, keep in mind that you cannot recruit Tali until later in the game. A common Mass Effect 2 Bastion Adept build:
4 - Heavy Warp
4 - Heavy Throw
4 - Heavy Singularity
4 - Pull Field
0 - Shockwave
4 - Bastion
1 - Stasis (Requires Lair of the Shadow Broker DLC)