Shall I just wait until I get a bit better? Or should I go for it
anyway? Or does anyone know of any groups or anyone interested in doing
the odd 15-20 m route? I'm very much a recreational cyclist (although I do
commute occasionally) and I enjoy going with people but don't like slowing
people down or otherwise inconveniencing people.

I was in the same position as you just over a year a go - furthest I'd
ridden was around 40 miles and I was just a (35 year old) 1000 mile a year
commuter.

Decided to take the plunge and tagged on to the local club Saturday morning
social ride (approx. 40 miles at an average 16-17mph with a cafe stop). My
first ride I found out that my maximum heart rate was actually 10bpm higher
than I thought it was! Second time I was getting left behind and no less
than the club chairman dropped back and towed me back on to the bunch. The
pace varies a bit depending upon numbers and conditions, and winds up for
the cafe stop sprint, but it's a good way to get used to group riding and
get to know people and other rides that are happening.

My club is, from what I gather, a bit unusual in that the Saturday morning
social ride does the same route every week. But there are plenty of other
options:

Saturday Social ride (as above)
Sunday Summer training rides - at least 2 pace options but normally 60
miles+
(some of these may just be little ring 16mph / Zone 1 + 2 HR, others at
sportif pace)
Sunday Winter training rides 60-80 miles @ 17-18mph average with cafe stop
Tuesday Summer Chaingang 40 miles @ 23-24 mph average (only stop for
crashes!)
Thursday Summer Time Trials
I think there also touring club rides as well.

I would assume that most clubs have a similar set up? Us southerners are
always told it's friendlier up north so I would be surprised if you could
not find a local club who are welcoming and have a suitable ride to start
with. With the exception of the chaingangs I'd say all rides I do go out
with a "leave no one behind" attitude - that means everyone stops when
someone gets a puncture. The times I, or someone else, have had to drop off
a training ride we at least check they know the way home and have some money
/ food and a phone.

Everyone takes a kicking at some point - I've taken a fair few this year,
mainly in races, and also ridden in some horrendous weather including racing
in the most torrential rain I have experienced in my life so far! But it's
the only way to get better / fitter and depending upon your goals you'll
learn a lot and get plenty of advice.

I'm definitely a "cool shade and carbon bike" roadie and have a decent
sprint, and I have started racing this year - which I had no intention of
initially - but can't say I've experienced any dishing out of deliberate
club hammerings and generally everyone is just out to enjoy their riding and
always encouraging.

So I'd say just go for it if you can find a "social ride" - you can minimise
any potential problems by knowing the route beforehand, choose one with a
cafe stop (so you can catch up and also get to know people) and take all the
usual bits like puncture kit, spare tube(s), money, phone etc.

Be careful though because it can get addictive and expensive!

I'd also say go and have a crack at a time trial even if it's just a "come
and try it" evening. Can be a different crowd but also welcoming and full of
encouragement for novices - the roadies will say it's boring but the testers
will maintain it's a truer showing of what you are really capable of.

For info, my first season achievements:
Reduced 10 mile TT time from a 25:46 to a 23:10.
Best 25 mile TT 1:00:19.
Won a 4th cat circuit race at Castle Combe and gained my 3rd cat.
Have managed to finished first and last in BCF races and club TTs in one
year!
Gone from owning 2 bikes to 5 bikes including significant amounts of carbon.
Now averaging at least 150 miles / 10 hours a week.
Still haven't ridden more than 100 miles in one ride though.

Good luck!

Regards,

Simon