Bike weight

i'd go for lightweight as one of the key decisions.

however; a cheap lightweight bike might be a bit spongy. i couldn't get on with a planet-x nanolight which was a very good price. i then sold it along with my left kidney and bought a cervelo r5.

the difference in ride quality and responsive was much more noticeable than i'd hoped. a really amazing machine.

it's fairly commonplace to get a sub 1kg frame these days. it's then the cost of the group and finishing kit that damage the wallet. i've got the weight of the cervelo down to around 6.2kg. it's an amazing piece of kit; when i'm fit and thin i feel like i can just honk up anything at high speed.

Overall weight, not too important, though you might feel a difference. The proportion of weight that's in the wheels is more important, so IMO that should be your priority.

Great bikes can be made of steel, aluminium, titanium, carbon, as can poor ones, so I wouldn't set out with particular preconceptions and rule out a bike just because of what its made of..

That said - 30ish miles isn't that far, so it may affect the comfort vs weight argument a bit too.

I have 3 mountain bikes - all reasonable weights, but with a noticeable weight difference between each one.

Riding and recording the same hills on strava I can clearly see that lighter = faster uphill, although I guess comfort is more important if the ride is viewed as a whole -I ride the middle weight one generally as the uber-light one is fully rigid and with an old antique Flite saddle and I reckon it'd hurt on longer rides)

If you're not racing then I'd say being comfy is a greater priority than counting grammes, and probably more efficient too, unless the bulk of your riding is in very hilly terrain.

Work out the weight difference between your current bike and the one you might buy, strap that amount in sugar bags to your bike somehow then go for a spin. See if you notice the difference.

I own a Scott S20 and a canyon ultimate c.f. 8 my canyon tips the scales at just over 7.3 kg and it's a joy going uphill however the Scott is around 9kg and although not as easy uphill , descents and continual flat riding take a lot less effort due to it's extra mass , horses for courses but for hilly or rolling rides I'd take the lighter bike every day , flat TTs or long pan flat rides it's the Scott .

Both alu and carbon have their merits just test ride a few of both within ur budget and make a decision that works for you , every person is different in what they want and how they ride