It's better to not have things that you feel wishy washy about.
ご質問ありがとうございます。
「あっても、なくてもいい」=「with or without it's okay」
「ものは」=「things that are」
「ない方がいい」=「better to not have」
この表現はちょっと訳しにくいですが、以下の言い方はちょうど良いと思います。
「It's better to not have things that you feel wishy washy about.」
「feel wishy washy about」は決まり文句で、「どうでも良い」と言うニュアンスがしますのでこの状況では的確です。「feel wishy washy about」の代わりに「feel uncertain about」も言っても大丈夫です。
ご参考になれば幸いです。
"It's better not to have things that are good to have but fine if you don't have them."
"It's better not to have things you don't need."
- "It's better not to have things that are good to have but fine if you don't have them."
"it's better ~" 「〜方がいい」
"not to have" 「ない」
"it's better not to have ~" 「〜ない方がいい」
"things that ~" 「〜ものは」
"that are good to have" 「あってもいい」
"fine if you don't have them" 「なくてもいい」
"that are good to have but fine if you don't have them." 「あっても、なくてもいい」
- "It's better not to have things you don't need."
"things you don't need" 「あっても、なくてもものは」・「必要がないものは」