You are welcome. Bike ownership is a very subjective and individual thing. Some people won't ride anything other than steel, for other it's titanium, and others carbon. One of the most long running arguments is with braking systems. In this respect it's not much different to buying a car. Actually this is quite a good analogy I find - that is saying the type of car you would choose to drive on a Sunday drive out if you were just out on your own.
Otherwise you'll find that people can only really give advice based on what they own and have owned unless they work in the industry.
It sounds from what you say that you are not looking for an out and out race bike, but something more comfortable with a useful turn of speed. I've never ridden a Synapse but those who have them swear by them as being well-made and comfortable.
There's no hard and fast rules with frame materials other than it is a good predictor of weight and goes a little way to predicting frame stiffness and ride quality, but there are no absolutes. I have two carbon bikes, one rides rather more plushly than the other. Weight affects acceleration and hill climbing but not flat riding performance so much.
Out of my bikes, I know when I'm on the steel one, it is harder work due to the weight. The aluminium one rides well enough, is pretty light and rides well enough. The carbon Emonda is the lightest and fastest. It's the bike I cherish the most, while the carbon Orro Gold STC is the most comfortable and my choice if riding more than 30 miles in one ride.
The Emonda had the chain off while I was climbing a hill under power (strange circumstances). I've just got it back from the carbon repair centre - £370 for a small repair. If you are working to a budget, want something light, fast, and enjoyable without the fragility of carbon, you'll probably better off looking to aluminium.
105 is a really good groupset, but Tiagra also works very well. Ultegra is that bit slicker than 105, but the difference isn't night and day.
Rim brakes are absolutely good enough for dry riding; if you intend to be a fair weather cyclist and happy to just slow down if you get caught in a shower, then rim brakes are just fine.
I wouldn't buy a bike that I don't like the look of, but some people just see a bike as a tool and things like colour just don't matter to them.
Ultimately your budget means that you are likely to have to compromise somewhere.
The Cube Attain is another bike you could put on your shopping list. The cheaper versions are aluminium and the more expensive ones are carbon.
The variations and permutations are endless.
Lastly Boardman are a brand I respect, you could do much worse than buy another. They can be difficult to hunt down via
Halfords, so one of the best places to look for one are on the
TREDZ website.
