I was given a bottle of Old Myers Dark rum bought on their holiday in Jamaica. I was about 18 or so and it was a pressie brought back to me by my parents from Jamaica. It was really cheap there but impossible to find over here. It was a fine rum to drink on its own, real smooth and IMHO a match for the finest Scottish single malt. Turns out it is sold widely on the Greeek Islands and other places in GReece too. The same people bought me a bottle back from a trip there too a few years later.
Since that time I have tried a few but I would say that my favourite right now is Cane Rock. It is a Jamaican rum from a single estate full of intense and sublte flavours and undertones. AIUI real west indies rum is kind of like Scottish single malt. Each estate on the larger islands has their own character and flavours. One side of the island of Jamaica has different soils to another part of the island and this apparently comes out in the cane sugar and the final outcome of rum. Barbadan rum can be different. Venezuelan rum is different as is cuban rum. They all have their differences.
I have not tried spiced or flavoured rum much. I am afraid I have the rum elitism that scottish single malt elitist fans have for that beverage. You would not see Islay distillers selling their single malts with banana flavouring so why should you do that with good rum. The answer is likely that you do not, that the flavoured or spiced rums are likely cheaper rum which needs the added flavourings to mask the deficit in flavour from the base rum.
If you live in Cumbria, Lancashire, Cheshire or Yorkshire and can get to a Booths supermarket then do so. They are starting to stock more and more rums. In among the flavoured rums are good sipping rum from single estates. If you do not like rum then give some of these a try if you can. Or there is a famous pub in Brixton that sells possibly the widest range of rums you will ever see in one place in the UK, certainly in a UK pub or bar. That is if it is still open and run the same. Also, I think the George the IV in Eskdale used to sell a lot of single malts but also a fair few rums too. That was sold on though so might not do this now. I hope they do but I have not been in for 20 plus years.