Wedding time too late?

We are having our wedding and reception at a hotel. Due to check in times and not wanting to have random hours of our guests to do nothing our wedding is set to begin at 5:30 to 6. Cocktail hour and then reception 7-midnight. I feel like it's such a late time for a ceremony to start but I also want to make sure people aren't rushed if they are staying at the hotel that night. Originally we were going to have it start at 4:30 but check in wasn't until 4. We asked about early check in, but due to the amount of rooms-it could not be guaranteed. Is 5:30 too late for a wedding ceremony???