[Desire Q&A, Help & Troubleshooting] zedmarcus:
Like you said, most of it comes down to personal choice. And before this turns into another "which rom is best?" "it's all down to personal choice" threads, I'll give you a quick rundown on some of the rom's that I've tried (and/or read about) and my own "personal" views on them.

Basically, there are two main types of rom's:

The first is Sense rom's, which are the stock or modded versions of the standard HTC rom's. Some people swear by them, saying that they have all the stuff you mostly need already on them, and that they have all of the bells and whistles on them to make them look flashy. Other people argue that they are full and bloated with stuff you will probably never need, and this leads to slowdown, lags and generally a less "free" android experience.

http://xdaforums.com/showthread.php?t=1315961

This is the Sense rom of the moment right now. Originally developed as a personal rom by Sebastiaan15, it's now one of the most posted about rom's. It's a 3.5 Sense rom (the most recent, apart from the newly announced ICS 4.0) that Seb is constantly (ie pretty much every day) updating. From personally trying it I'd say it's a good rom that has a lot of good things going for it, but there are still issues that are being found with it and Seb is constantly fixing and changing things. If you want the latest flashy Sense rom then maybe try it.

http://xdaforums.com/showthread.php?t=1318370

michaelm_007's 3.5 rom

http://xdaforums.com/showthread.php?t=1250815

coolexe's 3.5 rom

http://xdaforums.com/showthread.php?t=1016940

This is a very stable Sense 2.1+3.0 rom that has lots of users and good reviews. Being a mixed Sense rom it has the stability of a 2.1 rom with some of the bonus bits from 3.0 Unfortunately the developer baadnewz has stopped development on this rom and so what you get is what you get as there are going to be no new versions.

http://xdaforums.com/showthread.php?t=1045824

If you are an app addict you might want to try this rom. Droidzone has developed a 1.9 Sense rom that has Data2sd which means that you can dictate the amount of app storage you want. Although not the latest version of Sense, it is stable and fast and Droidzone offers good support.

(Look out for Sense rom's by Alex-V, michaelm_007, coolexe, Droidzone, tamirda, and Leedroid (who is also not developing for the Desire anymore) as these are experienced developers with great rom's available here on XDA).

The second types of rom's are the aosp (Android Open Source Project) rom's. These are non-Sense rom's that run the purest form of the Android operating system without the "bloat" of any HTC Sense over them. Whilst many would argue that they are not so pretty as Sense rom's, a lot of people would say that because they are back to basics (so to speak) rom's, they don't suffer any of the lag caused by the Sense programming. By adding a launcher (such as Go Launcher Ex) from the market they can be just as flashy as a Sense rom. Also aosp rom's are generally better on battery life due to not being as "heavy" as Sense rom's. These are my rom's of choice.

http://xdaforums.com/showthread.php?t=957291

miui-xj is a "different" type of aosp rom, that in my opinion borrows a lot form the Apple school of interface. If you are looking for something a little "different" it might be worth a try. I've tried this myself and didn't particularly like the design, but a lot of people like the visual aspect of this rom, along with the themeing side of it. Updated weekly, it is a well supported rom.

http://xdaforums.com/showthread.php?t=880465

GingerVillain 3.3 is a great aosp rom that the developer (Richard Trip) is very active in the development of (his girlfriend has a Desire so he'd better be :D). Offering a fast, stable rom that has added goodies courtesy of Cyanogenmod, I would wholeheartedly recommend trying this rom.

http://xdaforums.com/showthread.php?t=1229003

Although ihlades has now stopped development of this rom, I would say this is a very fast and stable rom that has no known bugs. This is also one of my favourite rom's and the one I am currently using (don't always believe my sig).

http://xdaforums.com/showthread.php?t=1227419

dGB is an extremely "light" aosp rom that has been developed by rootSU (a very active member of this community). Although not to everyone's taste as it is so very light, I found this to be an extremely fast and stable rom (thanks rootSU, I tried it last week and was very impressed, Redux2 dragged me back though ;)).

Mention must also go to Oxygen (not available here on XDA, but google it), and Cyanogenmod7.

As always (always!) it depends on personal preference.

The views expressed in this post are my own and I don't need to be flamed for putting them here. If I missed any rom's or developers I apologise, this does not mean they are not quality, it just means either I haven't used them or I forgot about them. Any mistakes I'm sure will be pointed out.

I would always recommend reading threads and researching for yourself. Also, experiment, try different rom's and see what works best for you.

I'm sure other users will offer differing opinions, but these are mine.

Hope it helps.