Ranger of Eos ! Replace mentor with 4 of those

taken the Squadron Hawk out.

Put in 4 Brave the Elements , removed Smite and Rebuke . Still needs a sideboard though...

Oh wow. We have a lot of work to do.

Champion of the Parish may seem good, but after a lot of testing, I found out that 1-drop Soul Sisters is pretty bad.

Squadron Hawk should all be mainboarded. Mainboard or not there at all.

Mentor of the Meek is a card not many people consider, and it could be an interesting innovation. Consider bumping up to 3. Martyr of Sands should be a 3x, so take out a Ranger of Eos for an extra.

Both Kabira Crossroads and Radiant Fountain are pretty ungood anywhere, so replace them with 4x Windbrisk Heights . Also consider 1-2 Ghost Quarter .

Path to Exile should obviously be 4x rather than Brave the Elements , which should either be at 2, or sideboarded as 2.

Oblivion Ring as a 3x is too much. I wouldn't go more than 2.

Spectral Procession is an easy 4x for your list.

Consider adding a single mainboard Sword. Pretty much any will do, however, Sword of Light and Shadow easily fits the best in this deck.

Finally, fix your sideboard. It's a mess right now.

If you want ideas, check out my deck Soul Sisters 2: Revenge of the Sisterhood.

Apparently my deck is awful...

Thanks for the tips anyway. :-)

Update :-)

I really dig soul sisters builds. I highly suggest getting Rest in Peace into your sideboard. And 4 Rangers and 6CMC Elspeth seem like tall orders for your deck to fill. Normally I suggest the 4 hawks mainboarded, but I like your flavor idea with the mentors, so kudos to you ; P

Also, why no Honor of the Pure ?? Feel free to view Sweet Soul Sisters if you'd like too ; )

+1 for Soul Warden AND for being a casual player like my self. If you can afford to add cheap stuff check my Folk of the North (Modern) deck for infinite token/life/life loss compo.

Felidar Sovereign

Why not add instants so you gain life? Angel's Mercy probably isn't the best but you get the point

Added Honor of the Pure to main.

Changed the sideboard to fit in 4 Burrenton Forge-Tender .

Elspeth, Knight-Errant

I would say put in elspeth. She gets you so much life with her tokens and she can make a creature swing for lethal! Also I would possibly suggest a Restoration Angel for more ten triggers. Also time token generators like Spectral Procession or if you really want to go ham Increasing Devotion !! Maybe some Silence in the sideboard, it's basically time walk... For less mana... +1 for soul sisters!!!

knight errant is 10x better in modern than sun's champion, don't even maybeboard sun's lol.

And another update... I'm going to play this deck next sunday at a Qualifier, so it's nearing a finish...

diatryma, you're probably right, but I believe the deck is getting expensive enough as is by now, and I don't own an Elspeth, Knight-Errant ...

ah that makes sense, I mean if you were ordering it errant is far cheaper but I understand =)

Score of the Qualifier of today: Three wins, a draw in a Soul Sister mirror, and two losses to two different Tron decks.

Squadron Hawks are sooo good with Martyr of Sands!

I'd run Kor Firewalker over Forge-Tender in the sideboard.

Also, if you're not on a budget, Archangel of Thune is great in Soul Sisters. It also usually runs 2 or 3 Windbrisk Heights

Update

good looking deck, I would move your Brave the Elements to the side to make room for 1 more of each soul sister(Soul Warden, Soul's Attendant). I would also replace the Return to the Ranks with Immortal Servitude in your side board.

check out my build for idea's:

White Grrl's