Odd you don't see the rehashed episode 4 story, abandoned on a desert planet without parents, a droid that escapes with hidden vital information, a canteen scene where they are discovered by the enemy, older male lead character killed by the main bad character, destroying a final 'death star' through a hidden weak spot. What part was original 
but as I said before I can understand why they played it safe
None of those things matter when you're watching it though (other than the Starkiller base thing not being original), because the characters, dialogue and action are done so well. Whereas the prequels may have had different story ideas but you didn't care because everything else was so poor. In any case, if you talk in such general terms you can make it sound like a complete rip-off, but when you get down to the actual details there are differences in all of those plot ideas, and plenty of new stuff (a female lead, a stormtrooper who defects, a father being killed by his own son, etc). It's a pretty lazy analysis just to say 'there's a desert planet, and a droid etc etc.'
In more general terms, it's not a case of 'playing it safe', but rather they have made a deliberate effort to bring on board a new generation of fans, who might know next to nothing of Star Wars. They were right not to make it a straight continuation from ROTJ with all the political backstories and the complex history of the Force and the Jedi v Sith etc, that could only be appreciated by committed Star Wars fans. When the original was made it was not some complex thing, it was a straightforward adventure, which had a bit of political stuff mentioned briefly, and a mystical element which while important, was only touched upon in basic details. If they had never made a sequel it would still have been a great film. What they've tried to do here is re-create that simplicity, start a new group of heroes off on their journey (and this kind of tale always has very similar 'tropes' involved in doing that - a nobody living in a remote place (Rey), an unlikely hero (Finn), people from different backgrounds uniting to take on some evil); and tell a story that you can understand and enjoy even if you know nothing about Star Wars. It's to get a new generation involved and feeling that these are
their heroes. Now if you want to get deeper into it, the details and the backstory are there (in the novels, comics, visual dictionary etc), but you don't have to delve into any of that to understand and enjoy the film - and it was the same with the Original Trilogy, people could see the first one, forget about it for a couple of years, then see the next one and still understand it. They have cleverly managed to please the obsessive fans who want all the details, the casual fans who just want a simple story, and the new fans who don't yet know all the history.
As for the suspension of belief, thats in response to a previous poster having issue with an individual scene or event, not the whole story. So its not equivalent to finding the prequels boring, its the equivalent of people hating say the gymnastic yoda scene. People are justified for finding that scene as laughable but people are told to suspend their disbelief for the milenium falcon just being on jakku and fully pilotable. Both scenes are a bit shit but people can't say that about episode 7 for some reason. Doesn't take away from the overall film but still shit never the less.
That's a poor comparison to make though. The Falcon being on Jakku was just one of those coincidences that are needed to move the story along in a fantasy / adventure - it's no different to the droids
happening to end up at Luke's farm, and then the red droid
happening to blow up so he ended up with R2-D2 - without that coincidence none of the story would have happened. (In fact the Falcon being there is quite feasible - it's not the first time it's been stolen or lost, it was pilotable because Unkar Plutt had been working on it - it's in the film - and Han found it because he was looking for it and knew who had stolen it).
Whereas, Yoda's lightsaber battles are ridiculous on so many levels. Firstly they look stupid, turning what should be dramatic scenes into comedy routines. Secondly, even by the standards of what the Jedi can do, the idea of being able to jump around like that
and fight skilfully enough against full-size humans stretches credibility too far. And thirdly, the rest of the time he walks around with a stick. So why does he pretend to be frail for 90% of the time?
As for not applying the same standards to Ep 7 as we do to the prequels - if you analyse the OT in detail, I'm sure you could find plot holes and things which don't make sense, but because everything else is done so well, most people don't want to get down to that level of analysis. Whereas with the prequels, the really obvious flaws which you notice straight away make it clear that they are poor - without any deeper analysis. If it was almost any other film people would just write them off as mediocre and forget about them, but because people like Star Wars so much and were so disappointed, they analyse them to a deeper level and point out all the plot holes etc. But you don't need to go that deep to realise that they are poor films.
