Should roundabouts in/around urban areas be banned outright??

I have thought similar myself. It's the proliferation of those small roundabouts you mention that are the biggest issue rather than the larger roundabouts on major roads I think. The "newer" towns like Swords, Carrigaline etc seem to get absolutely coated in them. Dungarvan is a headwreck to drive past. And let's not mention the Bóthar na dTreabh in Galway.

It is at least possible to do better for vulnerable users if we used designs more closely resembling what's in Netherlands. But land take is the issue there. Here's one in Haarlem: https://maps.app.goo.gl/kFLgBVqokasDspxm7 and more complex one here: https://maps.app.goo.gl/xFRtaWyzCyEjfc9e7 Or of course if we just keep the vulnerable users away from the roundabout altogether with dedicated segregated routes.

I think the only good reason I can think to not outright "ban" them is to allow a reverse of the priority for a given junction: to prioritise traffic turning right. It's also nice to not have lights and all associated junction complexities too.

Roundabouts cannot cope with large traffic volumes. They work well up to a point, then when they hit capacity they fail spectacularly in the form of total gridlock from cars stuck on the roundabout waiting for their exit to clear.

For busy or congested routes, scrap the roundabout. They only belong on lightly trafficked roads or regionals for the most part.

Sometimes they work. Keep them where they do. Some don't work. Remove those.

There is an oversized roundabout where Greenfields and Coolroe Meadows meet in Ballincollig. 90% of the traffic is straight through and the whole thing is absurdly overspecced for what is a minor junction between a main road and lightly used cul de sacs. It is also horribly unfriendly to pedestrians and cyclists

Cork City Council did have an active travel plan for the road which involved adding dedicated bus stops, separated bike lanes, traffic calming measures and a light controlled junction replacing the roundabout. Ballincollig tidy towns managed to get the plan scrapped because they use the roundabout for floral decoration. Really.

That was probably an exception given that it was a planned town in the 60s i think. Everything motorway roads and cars were all the rage then.

However generally in the UK you don't see large numbers of roundabouts close together in succession on the suburbs like you see here

The Clonmel & Tullamore "bypasses" are a necklace of roundabouts rendered dysfunctional by traffic volumes.

This UK design is good but it's possible to do even better if you smooth out the angle for cyclists, so they don't do more than around a 45degree turn when coming to the roundabout, which is nice for maintaining momentum. The Dutch had this figured out but the new Irish ones also look really good IMO: https://www.nationaltransport.ie/wp-content/uploads/2023/08/Cycle-Design-Manual_Sept.-2023_Low-Res.pdf page 147/149 here shows a nice one somewhere in Fingal.

Edit: I have yet to actually use one of these new Irish ones though, so maybe I should reserve judgement. But it looks good.

some of the busy mini-roundabouts / spot roundabouts are quite dangerous. For example, Strand Road in Sandymount in Dublin. There are a series of tiny spot roundabouts used and people swing right across them sometimes without any warning and way to fast. I've seen a few near misses, crashes and major road rage incidents as a result of this.

They work if everyone's driving very slowly and being sane about using them i.e. assuming a car or bike might not have 100% visibility - all it takes is one driver to approach fast and it's an issue.

You typically be driving along the road really slowly, enter the round about and someone will just swing straight across without any warning, assuming they've entered before you, which they usually haven't, and then they nearly slam into you and go totally insane blaming the driver who genuinely just saw a car coming out of nowhere at way too high speed.

I've encountered a few totally crazy drivers on those over the years, and it's always someone who drives extremely fast, swings right, assumes everyone else can predict their movements and then goes nuts when they nearly slam into oncoming traffic that had no idea they were going to enter that fast and turn right.

Ireland has absolutely no enforcement of speed limits really on urban roads, so in those areas where you'd assume a 30-50, it's often more like 60-70 or higher in my experience which renders those kind of UK-style features like spot roundabouts highly dangerous.

They're OK in housing estates or really convoluted situations but, they're inappropriate on roads where traffic won't obey speed limits and will inevitably drive agressively.

Problem with roundabouts is people who haven't a clue how to use them.

I do hate pedestrian crossings just on the arms of roundabouts. Yes, of course they're necessary, but they are dangerous. You have to try to focus on that whilst making sure no-one has come up your inside, and with narrow roundabouts you're trying to make sure your road position is correct so you don't nick the curb.

Yes of course you should be able to do all of this as a driver, if not slow down, but I can see how a pedestrian stepping out onto the crossing is more likely to get hit than on one that is not connected to a roundabout.