Maybe he was worried that Luke would go down the same path his father would, so he kept things vague. That was always my take on Old Ben -- he wasn't really guiding Luke to do anything, it was the Force. "Luke, your father was actually a dangerous madman who slew younglings. In fact, is the right hand man, that academy you were joining? It's Space Fascism, so definitely don't go and join it to be with your father." lol
On the topic of the other two -- Personally, I liked Kenobi. It has some sillier bits, but nothing IMO that isn't easily explained (as an example, there's a scene where young Leia is chased by mercenaries and she kinda dunks on them. People hate it. I think it was a clear example of her Force Sensitivity, so I don't mind it at all.) Its main shortcoming for me was the villains could have been better and Reva was a bit predictable. I didn't think she was as bad as the Internet did.
Ahsoka... I wanted to like. It had a lot of potential, most of my issues were that it seemed like they were filming a video game, but since we're not playing Ahsoka we end up just watching her interact with things we have no meaning for. Other than that, it was decent save for what they did to Sabine, which was just a disgrace to her character. Sabine was disappointing, over and over again. Overall, I think it has been my least favorite of the Star Wars shows as it has had the most visible quirks and awkward shots.
As a continuation of that story it's pretty decent and I'm excited for S2. But as a continuation of that story, the characters were not as strong as I felt they could have been. Time passed and people change, that's fine. This wasn't quite that though.