Friendship Items are definitely worthwhile. The only Ougi I've actually used was Glacial Gargoyle Lance, and it was God awful. Really slow run up, really weak, really long cooldown. I have Soul Reaper Scythe as well, but I've not tried that out yet. I should imagine the other two Gargoyle Ougis are also pretty poor. If you go for Durability Tickets, the +10 and +30 tickets are the most efficient to buy point-wise. Everything else just devours your points. I wouldn't bother with the outfits unless you're able to rake in 50k points daily. You can also get Summoning Tickets for the Kijimuna Maiden. PC users got a free ticket for her recently during the rebalancing update, and I can say she's pretty useful, and pretty cute too. The Kijimuna Sigil ticket (250,000 points I believe) guarantees you a Maiden. The Princess ticket (100,000 points) *can* get you a Maiden, but there's also a chance you'll summon a normal Kijimuna. I was unlucky enough to have that. Not tried the Empress Ticket yet so I don't know about that one. What else was there? The Accessory Box is a waste of points. Lucky Boxes are common enough to get for free, so I say leave them. I also advise against the Artisan boxes and Artisan Swords, since we get given one of those every login calendar anyway for free. That just leaves the Gacha Ticket I think. Again, we get given those for free in the login calendar, and from killing Kamui, so it's not really worth it unless you can rake in huge amounts of points.
That's Yuriko Hoshimura in the middle, with the Kiji Maiden "Rei" on the left. I'd like to get more Maidens if I can, but dang that's a lot of points.