Bigger franchise than Tomb Raider? Nopes.

First of all to be fair you should have put Uncharted 4 VS Halo 5 VS Zelda, now that's a hard one! From the ones you listed i'm sure Zelda is the obvious choice i mean come on it's not even a contest! Although maaaaaybe if Tomb Raider doesn't come to PS4 and only to PC eventually then the bump on Xbone should be bigger, but i would still have to say Zelda. Especially if they do a limited edition bundle for the holidays at 300$ it would sell like hotcakes.

Tomb Raider will not have a grat impact on xbox sales, after all we know it's coming to other platofrms as well (later).
I'd say Zelda and Bloodborne are almost equally important, they won't have a long lasting effect after release, but they're a both killer apps or in other words a they're a reason to own the WiiU or the Ps4. In that view they're both having an effect already on today console sales.

Probably Zelda is more important for the WiiU simply beacuse the console has less killer apps compared to the Ps4.

In therm of absolute console sales probably Bloodborne, it will boost the PS4 everywhere including Japan for a weeks, so let's say 100k PS4 sales extra due to bloodborne and let's say an average 33k in he 3 weeks folowing.

People why buy the Xone in holidays due to halo, tomb raider effect will be limited but will guarantee a 100k extra console sales

For Zelda it will sell 50k consoles extra on launch and 20k for the following 3 weeks and that will probably be it. Zelda has never been a great system seller, especially not on a system which isn't selling at all, like the GC.

And yet, Dark Souls 2 sold less than 2 million on 160 million combined PS360 user base...I think people generally underestimate Bloodborne's...niche-ness.

It actually isn't since Uncharted will have a bigger absolute impact on console sales due to it's popular in Europe as well as in the US, while Halo is mostly an US based game. The WII U will never sell like hotcakes though if that was possible either MK8 or SSB would have make that happen, but they didn't. Halo is to US is great, US is everything centered to be great in Europe, like most of MS games. And since Europe is almost as big of a market as the US these days the game which is extremely high anticipated in both regions on the most popular console probably takes the cake in absolute pointable console sales.

Now with a pricecut and the bundle for €250 with either sm3d world, mk8 or ssb included that would make a small difference 3 instead of 2.5 million sales. The last great selling Zelda didn't make it towards 7.5 million. So per game it is probably the least popular, so it would be responsible for the least actual console sales. Now if we talk about relative boosts in comparrison to the baseline Uncharted will end last and Zelda U probably first, since a 350k boost is almost impossible outside the holidays while a 100k boost is pretty much managable

Neither did the souls games recieve the advertation Sony has given Bloodborne

From an obj pov, we saw much more exciting things from bloodborne and barely anything from thé 2 others

So what dotés this poll tell US ? Thé vocal minorité is on forums

Zelda is much bigger than tomb raider. Even uncharted is bigger than tomb raide. 

Zelda will have the best attach rate without a doubt. And proportionately, it will provide the biggest boost. I think it could outright outsell both, but Bloodborne has hype behind it so I don't know. I'm completely unsure about Tomb Raider sales.