17 was actually not that difficult for me. At one spot my units got stuck in a corridor where no one could get past and enemies kept swarming but it ended up that xander was in front and just absorbed a lot of them basically. I can't remember how many deaths I had for 17 but it wasn't many I still had a majority I think and I was a lot less stressed than I was in chapter 10.
The traps were not even a problem because I have a lot of locksmith characters. I had Kaze, Niles, my master ninja corrin, and obviously saizo as an ally who needed pretty much no help on surviving on my part. And when a locksmith unit wasn't near by I just kept behind the traps and tried to repel anything that came through and possibly wait for a locksmith unit to come eventually.
But yeah I didn't think it was noticeably too difficult. It wasn't easy but it wasn't difficult. Also I had just finished doing 2 paralogues one for kana and one for midori (since I married kaze) so I had leveled my party a lot. I actually had most of my party die on the traitor ship level because the one before it was the 3 units one so it was a big level gap and to get the gold as fast as possible I split my party up 4 ways regardless of efficiency and allowed them all to be picked off for the most part.