Rigi vs Pilatus vs Titlis

Ranking for what? Beauty? Climbing?

I've only been up Pilatus but I loved it. We went up by cable car/gondola and down the other side by rack railway. It was wonderful. That was in summer, I've no idea what it's like in March. I've seen reviews of the other two and all were positive so it's hard to say which might be more to your liking.

I've only been up Rigi and really enjoyed it. The entire trip is included on the Swiss Travel Pass. You would take a boat ride across the lake to a cog train that takes you up to the summit. The views were amazing. There are various stops along the way should you choose to get off and look around. You can take a gondola down if you prefer that over the train. The boat goes to a small village, Vitnau. It looked like it might have been interesting to spend a bit of time, but we did not.

We picked Pilatus because we could make a visit there in half a day, whereas we judged that Rigi would have taken us all day because of the long boat and train rides. Not an issue if you have time. But you can also wait to decide when you get there and can see what the real-time weather is at each location. Ask at hotel. And make sure all the transportation is running and not closed for maintenance.

Stan makes an excellent point. Pilatus was completely socked in with no visibility the day we did Rigi. In fact, we hadn't planned to do Rigi that day, but suddenly it cleared over Rigi and we quickly made our way to the boat.

I'm sorry; I should have clarified criteria! Rankings on beauty, activities, time requirement, personal preference.
I appreciate the opinions stated above. We plan to check everything day-of for all activities because weather is so unpredictable during this time. Just getting an idea of what we would like to do (almost in an order so if one thing is closed, go down the list to the next) instead of coming up with plans entirely after arrival. It's a group of 6 who can be indecisive hence the planning on my part :)

While I'm here, any cliff walks/suspension bridges people recommend throughout the BO and Lucern areas?

The steep rack railway up Pilatus does not operate until mid-May or later.

I've been up Rigi twice - I don't do rankings.

Both times were fun - once in part cloud and once in heavy fog between the next to last stop and the top. It was clear when we started up from the lake.

The lake is wonderful.

I don't know what you will be able to do or what will be enjoyable for you in March.