If you have money to spare, sure, why not, buy them all. If you're asking if Titanfall is worth the price of the Xbox, in my opinion, no it isn't. I have a very powerful PC and the game for it from Mexican Origin site for about $45 including the season pass and aside from playing 2 hours at midnight when the game unlocked and 2 hours more after work that day I haven't touched the game since, nor do I get any urge to, instead I'm playing the alien coop game (cant remember the name of the mode) in CoD: Ghosts.
Titanfall is not a bad game by any means, it does what it tries very well, unfortunately what there is there it's not enough imo, and even though I paid $45 for the game and the season pass I still think it's too much, it should have been $20 as digital download, maybe $30, and certainly not worth the price of an Xbox One, especially so if you have a PS4.
Wait for Titanfall 2 which by then will hopefully be a more complete concept in what their trying to achieve and as far as exclusives for the Xbox One go, unless Microsoft spends a shit load of money like they did with Titanfall to make more 3rd party games exclusives, which I doubt they will, they have nowhere near the amount of studios that Sony has in terms of numbers of quality for that matter. The only ones they've got left are Turn10 which make Forza and Rare, a shell of what it used to be, so unless they open more studios or pony up more money I wouldn't expect any other exclusives any time soon.
Look if you have spare money or can justify $400 for Titanfall, sure buy it, otherwise wait for exclusive stuff to come out for it cos any third party games will always look better on the PS4 as they would look better on the PC for obvious reasons.