美しい信長の?

美しい信長よ!
そう、名前があるよ 
JKの名前は<大野>[おおの]ひさきだ。
DKの名前は <伊東>[いとう]はじめだ。
ひさきの名前は時々使われているけど、はじめの名前は全然使われていない。むしろはじめより徳川家康とよんでいる。
I pulled 次の月曜日 off Hinative, but the questions there tend to be entirely devoid of context so they might not always be the most natural options.
I think Monday might just be an example where it doesn’t really matter which you use since next Monday is always next week’s Monday (unless you’re a monster and you start your weeks on Sunday), but for other days it makes a lot of sense to make a distinction. After all, on Monday, 次の火曜日 and 来週の火曜日 are a week apart.
The way I understand them, つもり is about what you plan to do, while ことにする (or rather just にする - no idea why these are treated as two separate things) is about what you decide to do.
So there are situations where you could use both - if you decide to go somewhere tomorrow, you can say 明日は行くつもりだ or 明日は行くことにする. I feel like つもり emphasises the plan itself, and にする emphasises the decision you made.
However, にする is always about decisions you made, as I understand it, so if someone else made plans for you, you wouldn’t use it.
And likewise, when something isn’t so much about something you have planned but more just about a decision you make, it would feel a bit weird to use つもり. You could say 魚を食べるつもりだ in a restaurant, but 魚にする feels a lot more natural to me for saying you’ll have the fish.
In this particular situation, I think つもり might be a bit more natural, since the key element here (as I see it) is not the decision to go to the airport, but rather that going to the airport was planned at all, regardless of who made that decision.





Thank you for the feedback! 



.
)
. It’s not like we’re all writing in keigo.