In the short story I'm reading now (「ドライブ・マイ・カー」 by Haruki Murakami) there are two very similar phrases to express what I would translate as "too cautious": 「慎重すぎる」 and 「慎重に過ぎる」:
いささか乱暴すぎるか、いささか慎重すぎるか、どちらかだ。
彼女たちは多くの場合、慎重に過ぎる女性ドライバーたちを馬鹿にし、[...]
My question is: are those two phrases different in some way because having or not having 「に」 between 「慎重」 and 「すぎる」?
Also, why is 「すぎる」 written using hiragana only in one case and kanji in the other?