I've had a campaign idea that I've been wanting to make for a while now but I have one major obstacle stopping me.

BSPs

I am just going to flat out say it, my BSPs are terrible. My latest isn't too bad but it is an urban environment and I can get away with leaving things a little "blocky". My campaign requires natural BSPs like mountains, valleys, and swamps.

I completely agree that CE maps "especially" campaign maps, should not reuse BSPs.(sadly I was forced to reuse ratrace for my last map due to an exporting issue) However, would it be a more enjoyable experience to simply use the Combat Evolved BSPs in new ways/situations rather than walking through 5+ terribly made ones?

Like I said, I would really prefer to make my own levels here, but I know that a bad BSP can ruin a map. If my map comes out bad, I want it to be because it was just a bad idea, not because it has a horrible BSP dragging it down.

It's hard for me to decide, but I'm leaning towards custom. On the one hand,
-Walking through the same old combat evolved bsps really sucks.
-Some areas are designed around their encounters, and vice-versa.
On the other hand,
+Custom sp bsps can be designed and shaped however you want them to be, depending on the encounters.
-They could look bad depending on your modeling practice.

I realize that it's probably hard to develop new modeling techniques. I suggest you can import existing campaign bsps and base your level off of certain geometries in your own bsp... kind of like how CMT made the new spv2 bsps.
I can help you out (hassle-free) in making terrain. PM?

I don't care if your bsp looks like crap or not, if its fun, I would think a majority of the people here would still like it. Beauty is just a plus.

Anyway, theres a thing called practice and tutorials that comes in to play when creating things. Now's the time use it

Custom for sure. Just as long as it works. Like this:
http://hce.halomaps.org/index.cfm?fid=1575
Very basic, but still kind of fun.