1200 foot fiberoptic and power pull
I think in this case, I'd go with a direct burial armored fiber optic cable in the same trench, rather than running it in the conduit with the power.  Here is my reasoning.  

The all dielectric cable you can run in the same conduit with the power is not rodent resistant.  I would be concerned about rodent damage in your pulling points.  I think an armored fiber buried in the same trench will be safer.  

It will be much, much easier to install - almost foolproof.  No pulling the delicate preterminated ends through the conduit.  Put the spool on a pipe and have two people walk it down the trench and it will be laid about as fast as you can walk 1200 feet.  

The only problem is if the direct burial fiber ever gets damaged, it will be very expensive to locate and repair the fault;  but realistically, in that event, you can just install an all dielectric fiber in the power conduit and abandon the damaged cable in the ground.  

That is one reason to oversize the conduit a bit.  Don't try to go real close to the conduit fill limit.  That's a terrible way to save a few bucks.  Other reasons to oversize the conduit - easier pulling and leaves you with the option to install bigger wire later, just in case.  

Consider using the big sweeps for your 90° bends.  Large diameter pre-made PVC 90's are readily available.  

I'd try to keep the 90°'s to a minimum - go for straight pulls from handhole to handhole.  The telecom standards want you to avoid making bends in boxes, they recommend a straight through pull.  I think that guideline (it's not a code requirement) makes sense for workstation runs in EMT in buildings, I don't think it makes sense with a long underground run like this.  

For the power - its probably not worth worrying about in this case, but don't rule out aluminum.  Aluminum is lighter, so it creates less friction in the pipe and pulls easier.  It might save money.  Since you'll probably be terminating in disconnects at both ends, terminating is not an issue.  Your splices in the handholes will be easier with copper, since wet location wire nuts are readily available.  

In the comments, @Harper recommends limiting the distance between pulling points to 240' or 490' to stay closer to what's on a spool of wire.  I'd go a little closer if possible - say 220' - because the longest fish tape I have is 240'.  At least it was 240' when it was new, it has lost a few feet.  This may or may not ever matter,  just another thing to weigh in your planning.  

I always include a pull string when I pull wire.  With PVC, I do not use inexpensive polypropylene string for pull strings, it is too likely to burn through a 90.  I use mule tape, which is flat nylon, or scrap wire or cable.  It's mainly there as a last resort - I'd rather use a fish tape - but it's easy enough to pull one in and better to have it and not need it than need it and not have it.  

The three most important things when pulling wire:  LUBE, LUBE, LUBE.  Maybe you like the yellow waxy stuff (it freezes in the winter) maybe you like the blue goo like I do, maybe you prefer the new less-mess clear stuff, but whatever you do, lube.  Lube more than you think you need.  Way more.