I agree with OP, I was thinking of starting a thread on this topic. Deathclaws are too powerful and their attacks too frequent.
RE: Mr Handy. I've got 3 Vaults running. One for a little over 2 weeks, and two for about 10 days each. Although I've received dozens of lunch boxes through achieving objectives, and even purchased 15 of them, I haven't gotten a single Mr. Handy. So the only way I see of obtaining a Mr. Handy is to purchase a 5-pack.
RE: Deathclaw Death Pit Gauntlet of Death. Each of my Vaults has a different variation of this, and although it is an effective way to deal with Deathclaws, attacks always leave me extremely low on Stimpaks and Radaways, and if a Deathclaw somehow escapes the Death Trap, several deceased Dwellers as well. No sooner do I rebuild a "stockpile" of a couple dozen Stimpaks and Radaways than another Deathclaw attack happens that depletes them again (not to mention the toll taken by radroaches, molerats and fires). Yesterday one of my Vaults had 4 Deathclaw attacks within 2 hours. Bottom line is that although I'm able to survive the attacks, I'm unable to stockpile enough Stimpaks and Radaways to send Dwellers out into the Wasteland.
So I agree with OP, it would be nice if the Deathclaw Attack mechanics could be tweaked to be a little kinder to newer Vaults. And maybe increase the probability of a lunchbox containing a Mr. Handy.