I don't think a journal needs an entry every day to be worth keeping. Looking back through an old journal, a gap of a few weeks doesn't make the entries around it any less interesting. I'd rather leave the gap than feel obliged to backfill a load of days just to keep a streak going.
That's why I prefer an undated running format. Entries stay in order without a run of empty dated pages, and a simple date heading is enough to find one later.
Date headings handle chronology; page numbers and a short index for recurring topics or notable entries help when you remember the subject but not when you wrote it.
For date-based lookup, a monthly calendar with page numbers on days that have entries gives you a quick locator. The topic index can stay for subject searches, so the two aren't doing the same job.
A page range in the calendar square could help if you have more than one entry in a day, without cramming in every page number.
A page range is handy on busy days. I'd add it when I finish an entry, not make calendar upkeep a separate daily task. That's how a locator becomes unpaid admin.