That's good, that they are flexible, as many aren't.
I've some pension funds with Irish Life, that have been performing fine, overall, over the last seven years. I also have funds invested elsehere, through a buy out bond, which have also done well. Personally, I've no issues with Irish Life, but I have heard a few criticise them.
I think you might want to start off by identifying what you want, from a provider.
Questions might incl.
* The range of funds available, and ease to switch between funds.
* The level of support required / provided (by phone, email, app etc)
* The fees / charges applied, in return for the above, and related services.
Then, once I was clear on my criteria, I'd go online and research performance of specific funds (for example, you could compare a selection of higher risk specialist investment funds, like property (which actually is relatively high risk!). There are independent comparison websites available.
One of my friends is absoutely obsessed with trying to get the lowest fees, so he'd argue all day that Acorn Life are great, but when you try to ask him about their investment performance, level of support etc. he fails to persuade me, every time. I've no idea if they are the cheapest on the market, my friends thinks they are, but they don't give the options and level of support that I want etc. That's just an example, but no doubt you take my point.
There are a lot of people here with far greater expertise on pensions and the providers than I have, so no doubt there are further responses coming...