It's all about context... The franchise was nearly extinct, the studio gave it another try and put resources behind it, not only was it a financial success, it was nominated for 50 awards. considering it's success, yes we should be grateful for a franchise were fans of at this level.
Only Star Trek fans out of any genre fandom would look at a huge epic film coming up and complain. How much we take the franchise for granted these days, even after it almost disappeared for a third time not long ago. You can pick it apart, but it mainly matters if it's good entertainment, which ultimately ST in all it's incarnations is.
As for the negative reviews. They may well not have liked it, which is fine, but it smacks of the old popularity backlash...sometimes something is just too popular for the media to take, then they set upon it like wolves. It would have been almost unprecedented for the two JJ Trek films to have 95% approval at RT. There are already many glowing reviews.
I don't necessarily equate 'huge' and 'epic' with 'good entertainment'. All that means is that it had a big budget. There's plenty of mindless blockbusters to satiate that market.
Nor do I feel that we should be grateful simply to have any Star Trek available. I have almost every episode on DVD; they don't go away just because it isn't being made any more. We're not compelled to like something with the Star Trek label just because it's all that is being made these days.
I'd rather have no Star Trek than a bad Star Trek film, regardless of how big its budget is. Whether it is bad or not, of course, is in the eye of the beholder.