Yeah sounds like you've got the gist of it. HFT is a game of compromises and hedging your bets.
People tend to choose a setup that gives them to best chance based on their own strengths and weaknesses.
I'd advise going with a middle of the road setup until you've shot a few competitions and figured out what your strengths and weaknesses are.
Top of trajectory for a .177 is usually around 25 yards unless you've got really really high mounts, so if you zero at 35 you will need to hold under for some shots. Not a problem, though.
I advise a 25 yard zero for newcomers to the sport for lots of good reasons, but a 35 yard zero will work too. In fact you can zero at any range, it doesn't really matter to be honest.
One of the reasons I advocate 25 yards as a zero is that it means you'll be on your crosshair for the most difficult shots (in terms of MoA accuracy) and this can often be a help to people who aren't completely familiar with all of their holdovers/holdunders etc.
Best thing to do is not spend too much money on kit, spend a bit of time setting it up and then go out and shoot a competition.