The first thing that needs to be said is that time in the Funeral Zone is different for those who mourn. Time seems to slow down. Ordinary business is largely suspended and each thing said or experienced receives its full weight. On top of that, one is often very tired. There is much to do, and one may not be sleeping well, anyway.
This alteration in how one experiences time means that the sensitive pastor has to do funerals that take it into account. Short is better. It may seem too brief to the leader, but then "time on stage" always seems to speed up. "Audience time" -- especially "weary and grieving audience time" slows down. So when in doubt, trim it.
Keep in mind, also, that the entire funeral experience is one liturgical act. The gathering, the waiting for the funeral to begin while the music plays, the funeral itself, the filing-past-the-casket and last good-byes, the pallbearers carrying the casket to the hearse, the drive in procession to the cemetery, and the committal are all one whole. Each part can seem to last forever. That means that your ten-to-fifteen minute "funeral service" with its five minute sermon is part of an entire ritual act which will take at least an hour or an hour and a half to get through.
Now, if one comes from a liturgical tradition that is very wordy -- lots of beautiful words that everyone has heard and/or repeated over and over in their lives -- then you can get away with a bit of length. The purpose of ritual is to carry us when we have no strength. Low Church Protestants are severely handicapped in worship, because we must reach deep into ourselves -- often when we are frazzled or hurt -- to find the well of response which enables us to connect with God. People who are steeped in ritual words can hear the first line of a funeral liturgy -- or wedding liturgy, or communion liturgy -- and they're THERE. The old words have invoked the mood and responsiveness they need for them.
So don't cut short the good, old words. Marginally churched people, as well as Low Church Prots, need short funerals. Liturgical folk want and need all the "right stuff" to help them make the transition from Before to After. My bottom line is that when I get to the graveside, I always use the grand, old words from the committal service that the idiots who updated our Book of Worship dropped from the liturgy: "ashes to ashes, dust to dust" and all that. You see, these are words that carry them through that last farewell, and propel them back into the Real World and its sense of time. They say, in addition to the actual meaning of their words, "This is it. It's over. Life has to go on now." Likewise, saying The Lord's Prayer together at the graveside involves the people in doing something that jolts them out of their funeral reverie into taking charge again.
In addition to the funeral (in its wholeness), there are two other acts that sometimes get short shrift, but which are vitally important. The first is the visitation or wake. People are dropping these nowadays for convenience's sake or because they're exhausting. (When I was a kid, everybody did two nights of visitation. Oy.) But this is important. People need to acknowledge the place the deceased and his family have in their lives. And those who are in loss need to know that they are loved.
On a professional note, I don't like two hours' visitation right before the funeral, which is becoming common. That's because (as I said in my previous post) I want to attend the visitation in order to listen to the buzz before I write my sermon. I can't do that if we're just bang On.
The other thing that's really important is the dinner afterwards. My parish keeps up the tradition of the funeral dinner for the family. This is so important. People brighten up, the cloud lifts, life restarts around the sacred community of the dinner table. Not only that, but the Church gets to do something that shows their love for the family. All around, a thing not to be slighted.
False modesty that "doesn't want people to make a fuss over me" is simply ego, BTW. It's okay, if they don't want the community's attention. But they rob themselves and their neighbors of something important.
A word on children and funerals. Children feel grief as intensely as adults, but they grieve differently from adults. Funerals are largely an adult experience, with adults sharing old memories, adults conferring with each other on who goes in what order in the procession, etc. etc. Children are often just along for the ride. I lost two grandparents and a great-uncle when I was eleven, so I know this deal.
It is my opinion that children should attend funerals, though the younger they are, the less they should be expected to sit through them. Get as much "grown-up" response as you can from them (it's good training for life), then let them go play in the funeral home break room or the church nursery. Older children and youth can be given parts in the funeral, as readers (but only if they want to) or pallbearers (honorary if they are too young to carry the casket, but let them walk in the procession). The pastor should always note how the children are doing, and speak to them at the visitation: he is their pastor, too!