We've done big parties at home and at private locations.
It depends on your budget and the party purpose. For us, our daughter is a Christmas baby and we celebrate her birthday on her birthday the 27th. It is surprising how many parents are ready to drop kids off and go chill out a couple of hours that close to Christmas!! She has not had a bday party since her 13th when she wanted a dance party and we did that at the club. Most birthdays after that were us going to dinner as a family or her going to dinner with a group of her friends. All other parties were just social parties.
We've also done very large back to school parties, end of school parties, Halloween parties, July 4 parties and crawfish boils. I've had 125+ people in my backyard at a crawfish boil which was most of our block and families.
I've done several parties at my home where I catered food and I've had as many as 80 teens at my house (OUTSIDE). Depending on the ages and number of parents who stick around, I have also hired an off duty officer or 2 starting around age 13 just to ensure things went smoothly. This was especially helpful when the parties had teens around 16 or so. Around here, it is a common thing to hire officers to be around if needed and if a teen leaves the party, they do not come back. Safety issues regarding alcohol, etc. Parents are notified ahead of time that officers will be in attendance and if their child leaves the gated area, they are gone for the night.
I realize your child is 6 and not yet ready for the off duty officer but you are headed in that direction for later years so think about that. It is cheap $100 or less and you have authorities right there to help you if something gets out of control. We've never had an issue and we started this when we had a party at the country club and it is a club rule there to have officers on hand. I like that rule.
When daughter was younger (3-7ish) we had several themes.... magician, petting zoo, a monkey that entertained and loved attention. We usually hired a DJ for parties as well because they helped with games and prizes for everyone.
Have fun.. Just remember to figure out your limits, set the limit and stick with the limits. Sometimes it is fun to just have a small party and there is nothing wrong with that.