One thing to bear in mind when considering the travelling time from the church to the venue is the time of year, especially between early October and mid-March, in relation to good outdoor light for photographs.
Perhaps you chose your venue partly because there are beautiful grounds or landscaped gardens for photographs and if so it would be a pity not to be able to use them because it was nearly dark when you arrived there.
No matter how you go about it, from the time you walk up the aisle until you have finished greeting your guests at the door as they leave the church you can allow 90 minutes, perhaps another 10 minutes before you drive away to your venue.

In October the good quality light for outdoor photos is fading from 5.15pm early in the month to about 4.45pm later in the month.
In November those times are back to about 4.45pm early in the month to 4.15pm by the end of November.
In December those times can be anywhere from 4.15pm early in the month to 3.45pm by the end of the month.
These times are for bright days, if the weather is dull you can lose a further 20-30 minutes.
January will be similar to December, February will be similar to November and March would be similar to October.

A scene may look bright to the naked eye but this can be deceiving as our eyes naturally compensate for fading light. 
As the light fades a photographer is left juggling camera settings to keep everyone in photographs sharp and in focus with no movement showing.

Some photographers can take up to an hour with outdoor photographs so bear that in mind. If your photographer takes as long as that you would have to be starting the photographs up to an hour before the times mentioned above.

Ask your photographer at your initial meeting how long they normally take over any outdoor/indoor bridal party, family and group photographs so that you can bear that in mind when choosing a photographer. 

Most photographers, myself included aim to get those photographs taken in 30-35 minutes so that nobody gets fed up and everyone can re-join the rest of the guests at the drinks reception. The photographer can then continue capturing a great selection of casual/candid photos as you mingle with your guests before dinner.

I hope this may be helpful to some of you
David McLean
www.dmcphotography.ie
[email protected]
ph. 086-0684415