Well, that explains that I guess. Bail Organa had been saving Leia's life from day one, and naming her son for him would've been a fitting tribute. Kenobi did save them by sacrificing himself to buy them time to get off the Death Star, but one could argue that during the Rebellion they were saved countless times by all kinds of people. Why not Mon Mothma? Akbar? Dodonna? Wedge?
Naming Kylo Ren after Kenobi was fan service, which is something only the old fans are supposedly to like or demand. It's not the worst thing in the world, but it felt odd to me that Leia and Han would name their son Ben when Han had little interaction with him. If Kylo had been Luke's son, just like the EU, no problem.
Of course in the real world people name their children based on all kinds of reasons, but when you are naming a character as a call back to a past film or past character I didn't feel Kenobi had been in their lives long enough to get that honor, unlike Luke, where Ben was an integral-if not the integral-character in Luke's life.