Looking for a high value entry road bike

I'm looking into buying my first road bike, coming from a rigid 14 speed mountain bike frame (trek mountain track 800) which I upgraded to be fairly good on the road with a 52t crank, despite how heavy it is (\~43lbs/19.5kg with frame bag and rack). My budget is up around 1500$ USD, but lower ideally. I usually do rides of 25-50 miles, and typically average about 14-16 mph, depending on the hills, as the increased weight greatly slows me, at least I think.

I've looked on the used market, but since I'm relatively tall (74in/188cm), most of the bikes are too small or have fewer speeds than I would want. Since I'd like this bike to last me for a long time, I am trying to get something with a 10 or 11 speed groupset so I won't feel like I need to upgrade. Hence, I have found the following two options which I think are pretty suitable, but I am stuck on which to choose, if either. Also, it seems like going to any bike shop will definitely get me less value than what I can buy online, but I am open to being proven incorrect.

[Motobecane Immortal Spirit](http://www.bikesdirect.com/products/motobecane/carbon-road-bikes/carbon-road-bikes-immortal-spirit.htm): 1500$ USD

Pros: Full carbon, full Shimano 105, Lighter (19.1lbs/8.7kg)

Cons: Rim brakes, higher price, obscure brand, ships in two months

[Triban RC520 Disc](https://www.decathlon.com/products/road-bike-disc-105-rc-520?): 1200$ USD (1280$ after shipping)

Pros: Mechanical hydraulic disc brakes, cheaper, more mounting points, ships now

Cons: Heavier (\~24.1lbs/10.9kg), aluminum frame, (reportedly) not very good wheels, some non-105 groupset components

My primary concerns with the Motobecane are the rim brakes, as on my current bike the braking power is very underwhelming, especially on steep descents. As for the Triban, people online claim that the wheels which it comes with are not very good and will need replacement after not that long, which would easily make up the price difference between the two. Finally, its also 5lbs heavier, which I really don't know how noticeable or impactful it will be, but I am worried about if I ever try to do any racing with it.

If anyone has any insight or advice regarding this, or any suggestions as to bikes that fit my criteria better or similarly, or even if I'm concerned about the wrong things, it would be greatly appreciated.