I've had great success applying these variants to ensure that each round will have at least one treasure (diamonds or relic) and that there is enough "reward" to logically ask the question, "'Who is in' and 'Who is out'?":
1) As the "guide" (whoever is flipping the cards over for that round) starts to lead the group into the ruins, we don't consider that we have entered the ruins until the first treasure card is flipped over and therefore any red "danger" card is set aside.
*So, to describe it as if it was an actual game play, it might look something like the following: [Guide] "So, we're walking up the steps of the ruins and... " [flip - it's a mummy] "we encounter a mummy. Don't worry - we easily see her and hit her on the head with one of our walking sticks and she tumbles down the steps." (this card is now set aside (face-up) but not where the normal line of cards will ultimately be set down. Play continues "As we keep going, " [flip - it's a fire card] "one of you guys accidentally bump into a burning lamp stand and it almost falls onto our entire group! Thankfully we were able to see what was about to take place and we stopped it just in time." (this card is now placed next to the mummy card). [flip - it a treasure card] "But, as your very capable guide, I have safely brought us into the ruins where you can feast your eyes on treasures such as THIS!!!"...
**Once a treasure card shows up (even if it just for 1 diamond) then the entire group is in the ruins and all dangers at that point come into full effect.
2) Finally, the "guide" doesn't ask who is "in" or "out" until there is at least 5 diamonds that could be collected by someone (taking into consideration what might have been placed in front of each player's tent as well as what is on the "path").
Hopefully either or all of these variants can help this game to become very enjoyable for your group as well!
I don't see the point of the second variant and the first changes the game a bit too much for me.
If you have a number of hazards removed before getting started then it changes the odds considerably. It might even conceivably make it impossible for an expedition to fail.
The randomness of the number of successful rounds adds to the game I think. If a round completely fails then in effect the game is shortened. Having low treasure games allows scoot and run tactics to work (ie leave early with modest treasure off the cards). If you skew the game towards more treasure then that tactic becomes less effective.