To me, it is close to impossible to say which combination of tonearm and cartridge is really going to work in any system without an actual trial. Unfortunately, such actual trial before purchase is almost impossible to arrange.
I have not seen or heard the Talea arm. I am familiar with both the Titan and Orpheus L (I own both), and have heard both the Titan and orginal Orpheus in the Phantom arm. I have a Basis Vector arm myself. With this arm, I like both the Orpheus L and my Titan (not Titan i), though they sound quite different.
My friend had both a Graham Phantom arm and the Basis Vector arm on his table and would swap a Titan i and orginal Orpheus (not the low output version) between the two arms. For whatever reason, he much preferred the Basis arm with both cartridges and preferred the Orpheus over the Titan i. I really think this is all a matter of system matching and taste. I did not hear the direct comparison myself, but thought the Phantom sounded quite good with both cartridges. This friend ended up selling the Phantom arm. Another aquaintence who is very familiar with the Orpheus positively hates the Phantom arm and claims that the older Graham arms were superior to the Phantom (he characterizes the sound of the Phantom as unengaging and cold sounding). I have not otherwise heard anything bad about the Phantom and consider this very much a minority opinion.
As far as your purchase of the Titan i, I think it will make an interesting contrast with the Orpheus L. In my system, the Orpheus L has, in comparison with my Titan, a slightly more prominent upper midrange. This makes female vocals a bit more prominent and forward sounding. On well done recordings, this prominence can be seductive, but, where the vocalist is too close to the mike, the overloading is more annoying with the Orpheus than the Titan (more like the singer is shouting). The Titan has a slightly more open top end than the Orpheus, something I like. The bass response of both are quite different. The Orpheus has a very fast, punchy and dynamic low end (great with kick drums). But, that kind of tight bass response can sound a touch "toneless" and make the bass sound a bit disembodied. In terms of bass "tone" I actually prefer the Titan. Both cartridges are very good with minimizing the annoyance of surface noise; perhaps the Orpheus is a little better. If you have any issues with not having enough gain, the Orpheus is noticeably lower in gain than the Titan. I really cannot say which cartridge I prefer. I don't have an easy way to switch between the two (my Basis arm is not easy to setup properly) so I currently use the Orpheus L because it is my newest acquisition. I envy your ability to easily switch between the two. Both are terrific sounding and sufficient different in sound so that the combination makes a lot of sense.
