I believe in run-off elections. When no candidate gets over 50% of the vote, there is no way to determine who the voters want as their candidate without having a run-off. The delegate system is an imperfect form of run-off, but it’s better than saying that whoever gets a plurality (but not a majority) of delegates becomes the presumptive winner. A plurality not being enough has been the rule since the beginning of conventions and is the same rule we have for the electors in the electoral college.
Cruz won his Senate race in a run-off after losing to Dewhurst in the first vote (Dewhurst was in 1st place but with under 50%). Just one example of many run-off elections held in states where that’s the law.
The voting is not complete yet. The biggest complaint people had about the primaries before is that the whole thing is over before their state gets to vote. They feel disenfranchised. They don’t have that complaint this time.
There is no way Cruz can be mathematically eliminated even on the first ballot until California votes, if I understand the convention rules correctly. He can pick up all the unbound delegates (over 100) and get all of Rubio and Kasich’s delegates if they release them, all of which I believe could vote for Cruz on the first ballot.
The party is not united behind Trump, and that has way more to do with Trump than it has to do with Cruz.