That’s a medium-length story, but the TLDR is as follows.
There are many hybrid systems. Hybrid systems vary widely, at least in procedure, but I think also in outcome. I would prefer any of the hybrid systems currently in use to FPTP, and (with a few caveats*) I think you should, too.
The Scottish Parliament, the Welsh Assembly and the London Assembly are elected by different hybrid systems, but all three share the following features:
1) FPTP as the constituency system
2) a fixed-size top-up
3) top-up lists chosen by parties, in the order chosen by parties
4) a compensatory top-up (one which corrects disproportionality arising from constituencies by allocating a party a smaller share of top-up seats than its share of votes if it is over-represented in constituencies and a larger share if it is underrepresented)
None of these features is universal among hybrid systems. A compensatory top-up enables proportional representation and is, therefore, clearly preferable to a non-compensatory top-up, but the value of the other three features is debatable.
The Swedish Riksdag system doesn’t use FPTP as its constituency system. Instead, it uses a broadly proportional constituency system and a top-up for improved proportionality. This might or might not be better than the UK’s hybrid systems. (AV+ also uses a constituency system other than FPTP, but as far as I know it’s not in use.)
The German Bundestag (federal legislature) system has a variable-sized top-up, which more reliably produces very high levels of proportionality. This might or might not be better than the UK’s hybrid systems.
The Baden-Württemberg Landtag (German state legislature) system doesn’t use a list for the top-up, but instead corrects disproportionality by awarding seats to constituency runners-up. This might or might not be better than the UK’s hybrid systems.
Japanese legislative elections use a hybrid system with a non-compensatory top-up, preventing it from being proportional, but reducing the level of disproportionality.
*I think the main disadvantage that can affect a hybrid system is an inadequate top-up; too few top-up seats and divided into too many regions can reduce proportionality. Larger constituencies might also be a perceived disadvantage of hybrid systems; for example, switching from FPTP to a hybrid system with the same number of seats of which half came from a top-up list, would require constituency sizes to double. A threshold (as applies in London Assembly elections) below which parties are awarded no top-up seats can be a perceived disadvantage, but so can the lack of such a threshold; thresholds can help to limit fragmentation, but at the cost of more wasted votes and less proportionality.