General traveling with photo gear is always a compromise.
Bringing ALL my gear, lets me cover most anything I run into. But the bulk and weight is prohibitive, for two reasons:
1 - As you get older, you cannot carry as much weight as a 25 year old.
2 - Your travel mode may restrict how much gear you can carry, by bulk and/or weight.
So I compromise in what I bring to what I can reasonably carry.
You have to compromise on what you bring to what you can comfortably carry, for every day of your vacation.
- What feels easy to carry at home for a few minutes, may be too HEAVY after a few hours.
- What feels easy to carry on day 1, will very likely feel HEAVY after 14 or 21 days of constant carry.
- HEAT will make it feel even heavier. Just carrying a 35mm slr with one lens was tiring, in the hot summer Florida heat and humidity at Disney World/Epcot.
The old 80/20 rule applies to travel photography.
You can shoot 80% of the stuff with only 20% of your gear, if you pick right.
And how important is that last 20%?
You plan the best you can for where you are going and what you are likely to shoot.
Make your decision and live with it.
Example, shooting with a 35mm film camera.
- There were a few times when I wanted a lens wider than my 24mm lens. But that would have been another lens to carry, and get used only a few times. So I lived with the 24 as my widest lens.
- There were a few times when I wanted a 50 f/1.4, but that was another lens to carry that would only be used a few times. So I lived without a f/1.4 lens.
- There was ONE time when I wanted a 400 or 500mm tele, but it was only ONE time in many trips. So for all the other trips, it would have been unused baggage. I made do with my 200mm.
- I would have loved to have my flash, bracket and High Voltage pack, but it was way too much to carry, so I just brought the small shoe flash.
Other "general" comments and summary:
- As you get older, your ability to carry a load decreases. So you have to trim down the kit.
- I would not carry ALL my lenses. Too bulky and heavy, and some of the lens would not or rarely get used.
- I would not carry a 70-200 f/2.8. Too bulky and heavy. The f/4 lens is about half the weight. Or can you do without that lens?
- I would not carry my full flash kit. Too bulky. I would carry just a shoe flash.
- I would not carry my heavy tripod. Too bulky and heavy. I would carry a smaller/lighter 'travel' tripod.
Note that this is all for "general travel photography."
If you are going for something specific, like wolves in Yellowstone, then things are different, as you need specific gear. And in that case it will be LONG lens(es).