I'm only familiar with the 4E version of Eberron, and the one book I read, The City of Towers. It sounds to me like you're talking primarily about the Sovereign Host religion, so that's where I'll focus my answer.
Religion Can Improve Your Life
I'm not sure why you say that 'the gods are silent'. I don't recall reading anything anywhere that gave me that impression. There are divine characters in Eberron, and the fact that they can do divine acts using their god's power seems like pretty good evidence that these gods exist and that devotion can have tangible benefits. There are also a number of references to common folk saying prayers to the host in the hopes that it will improve things such as crop yields.
Religion Can Improve Your Afterlife
In the 'The Planes' section of 'Chapter 7: Gods and Cosmology' of the 4th Edition Eberron Campaign Guide, in the 'Dolurrh, the Shadowfell' section (page 262), it says "Some say that the ultimate fate of souls is to remain in Dolurrh and fade into the shadows, while others cling to a hope that souls eventually pass beyond the Shadowfell, beyond even the Astral Sea, to the place where the gods reside." On page 241, The Temple of the Wyrm Ascendant is mentioned. This sect of the Sovereign Host is popular in Stormreach and among dragonborn. It teaches that the sovereign host is composed of ascended dragons, and that you too can join them through your actions. So, it would seem that the 'idea of a pleasant afterlife' is indeed important to some people in Eberron, and that those people are able to hope for one. On the other hand, in the Sovereign Host's 'Practicing the Faith' section (page 242), it says how Vassals (devotees of the Sovereign Host) believe that their soul is a tiny spark of the divine that fades over the course of a mortal life, preventing them from returning to the gods. It goes on to say that, "Because Vassals foresee no reward in this afterlife, they consider the blessings of mortal existence much more important."
So, it seems to me that people have a reason to worship gods to improve their mortal lives more than to improve their afterlife, but that it wouldn't be unheard of for someone to believe their actions will affect their afterlife as well.