I'm not sure on the 35 blinks thing, but coming from a tech, I can see that as a reliable source. I personally would not change it, but if someone in here would like to try and find the lowest dwell setting for a stock ion, then that would be nice and we could ammend that part.
As for the bolt and QEV upgrades, the two things do have other added bonuses. I mean, we could argue either way that the marker needs no upgrades as 15 bps is all you need, honestly. But the QEV not only allows for a lower dwell to increase bps and efficiency, it allows acts as a grease trap for your gun. Excess lube that would have gone down into the solenoid and such is instead released through the QEV to provide easier cleaning. If youre ok with a little lower efficiency/higher dwell and doing a bit more cleaning on your gun every once in awhile (its not that often), then you don't have to buy the QEV. But for $20, this little piece is a steal. I do recommend when upgrading your marker that you buy the necessities first, such as a trigger, feedneck, and ASA, but when you get down to performance, unless something is really screwed up/a lemon and you need to replace it, the QEV is going to be your best bet for first place.
A new bolt also helps increase efficiency through sealing the dump chamber (dual tail orings). But added perks are much less kick and smoother operation. Some bolts may be quieter when firing as well.
So yes, in my opinion, the two upgrades are worth the money without a new board. But it all bubbles down to what is important to you
But, do remember that upgrading your gun is your choice. If you're happy where you are, then you dont have to go and buy these parts, they are just suggestions for the future