DedWards

Yay. Glad to help :D

I think I may have found a problem. You have a lot of effects that force a shuffle, not search. Ob Nixilis's ability requirs a search. Cosi's Trickster, on the other hand, does trigger for each shuffle.

The biggest problem with search effects, is most are optional. Maralen of the Mornsong is awesome because it's effect is a must :p

Ghost Quarter to force a search and shuffle.
Archive Trap for another use of any searching the opponent does.

No Setessan Oathsworn? Also, I'd personally take Seeds of Strength up to 4x and find a way to include Solidarity of Heroes. I've found that unless you use it for pumping a mass of token creatures, Phalanx Leader isn't as great in practice as it is on paper, or at least, that's how it's turned out for me.

You seem to be only ramping into Planeswalkers, but they can only activate their abilities once a turn, so I think The Chain Veil could help you a lot here.

Also, Painter's Servant isn't doing much here. In fact, it's causing Ancient Stirrings to become a dead card. I understand it works with Ugin's -X, but making one of your cards useless doesn't sit well with me. Maybe move it to the sideboard?

Goblin Electromancer to lower to make the spells cost {1} less, thus possibly making the deck trigger a turn or two earlier.

Lotus Bloom in the opening hand almost always gets Dragons Storming on turn 4

Sadly, Rite of Flame is banned in Modern (as is Seething Song). Makes me very sad, because I also have a Dragonstorm deck.

Soul's Fire is another 'Fling' you could use, though Soul's Fire doesn‘t require you to sacrifice the creature, so you could attack, Soul's Fire, then Fling :p

Here's a rough draft for an Owl Tribal deck:

http://www.mtgvault.com/dedwards/decks/owl-tribal/

A few cards your friend might want to consider are:
Pillory of the Sleepless - Locks down a creature and makes that creature's controller lose 1 life a turn.
Blind Hunter - 2/2 with flying and Haunt that drains 2 life as it enters the battlefield and when the haunted creature dies.
Mortifiy - While not as good as Unmake, it works nicely with Blind Hunter's haunt and can destroy enchantments.

If she does want to use these gold cards, I highly suggest adding some dual lands (Scoured Barrens?) and or fetch lands (Terramorphic Expanse or Evolving Wilds). These lands can even help increase the chance of having both colours for Batwing Brume.

If you'd like to take a look, here's my favourite BW deck that I run from time to time:
http://www.mtgvault.com/dedwards/decks/strong-hold-on-discipline/
Though, I don't run the Contaminated Bonds anymore, I can't seem to remember what I put in its place.

I don't know if you are, but I'm a little concerned about BW Tokens sticking around. Gatecrash gave Illness in the Ranks and now Dragons of Tarkir is giving Virulent Plague. That's very specific hate ._.

All Sundial of the Infinite does is allow Mimic Vat's copied creature to last until the end of the next players turn.

So, a bird tribal with all the birds having pictures of Owls... Hmmm... I'll have to get back to you on this.

Serra Avatar is a cool mid-late game card in any life gain deck, but for early game, Serra Ascendant is awesome. Other options include:

Creatures:
Hopeful Eidolon - Nice early game and it can Bestow late game to give Serra Avatar lifelink, thus practically doubling it's power and toughness each time it attacks (after dealing damage)
Nip Gwyllion - Not much use in here, but if you ever go black white, it's quite good.
Rhox Faithmender - its ability is self explanatory
Voracious Hatchling - another good one for black white, but not as great with only white cards.
Divinity of Pride - Another good mid-late game option, but I wouldn't use it and Serra Avatar in the same deck.
Martyr of Sands - frigging awesome for explosive life gain. Block, sacrifice, reveal your hand, gain lots of life. (lands are colourless, so they don't count)

Non creatures:
Dawn Charm - Your choice of 'fog'; regenerate a creature (to save it from kill spells); or counter a spell targeting you (like Skullcrack).
Spirit Link - I've checked the rules on this one, and it's not 'lifelink', so its ability stacks with any other life gain effect the enchanted creature may have.
Spirit Loop - see Spirit Link above. Also, this one can come back from the graveyard to your hand.
Brave the Elements - Saves your creatures from targeting spells and mass damage for the turn. Can also make your creatures unblockable for the turn, if the all opponent's share the colour you call.
Chalice of Life - once flipped (Chalice of Death), it eats chunks of the opponent's life, so it makes for a nice finisher.

Lastly, I'd like to say that Oblivion Ring is broken.... That's why I have 8 of it :P

I told you others would suggest Craterhoof Behemoth. Like I said, it's a good card, I just personally (and stubbornly) prefer Ezuri, Renegade Leader :p

I've been playing elves since Lorwyn / Shadowmoor, so most of my advice comes from personal experience. Because I've been playing elves since then, I already have the cards, so I forget that some of them have higher than expected price tags :| Currently, my token variant only costs about $82 and the Warrior based, aggro variant is about $67. So ya, not excessively pricey, but still a high-ish price.

Some people may suggest stuff like Craterhoof Behemoth, which is a good card and a good choice, but I just prefer to pump the 8 mana needed for it into Ezuri's 'Overrun' effect. But that's partially me being stubborn , and partially because I don't own any Craterhoof Behemoth :/

Hmmm... Doublers like that are nice, but I'm not sure it's necessary. Remember that the double from the furnace works both ways, and that could become a problem. If you absolutely need to double, the only one I'd use is Overblaze as it's controllable who or what takes double.

Pyrohemia then?

Boros Reckoner is strictly better than Spitemare, but nothing is stopping you from using both :P

I didn't mention it before, but some "obvious" cards you're not using are Lightning Bolt; Lighting Helix; and Boros Charm. While the charm can't target creatures with its burn option, the indestructible option is very nice.

Not so much what I "want", but I do have a few suggestions:

If you swap your lands out for snow covered lands, you could do quite a bit of damage with Skred.

Shivan Meteor does 13 damage to a creature and it can be suspended.

Blasphemous Act would be a cool sideboard card.