I have used Francesco's Optional New Items and Optional New Creatures mods and liked them both, but I'm wondering if there are equally good, or better, mods that would add new items and creatures to the game. I'm not looking for a game overhaul here--I still want to use Francesco's basic mod ("Leveled Creatures-Items")--but it might be fun to have an alternative to his two optional mods. Any outstanding recommendations?

If you want new creatures, this is definitely one to get. AFAIK, it's fully compatible with Fran's. But don't quote me on that.

http://www.nexusmods.com/oblivion/mods/17784/?

I can't help you with items I'm afraid.

Mart's Monster Mod is great, I've played with it in the past.

One I've been interested in playing but never got around to is http://tesalliance.org/forums/index.php?/files/file/1318-wac-waalx-animals-creatures/.

I've also always been a fan of http://www.nexusmods.com/oblivion/mods/18417/? and http://www.nexusmods.com/oblivion/mods/25309/?, both of which distribute new (recolored like in Fran's) armors into the game.

http://www.nexusmods.com/oblivion/mods/35560/? is kinda neat as well.

I use http://www.nexusmods.com/oblivion/mods/45522/? (note requirements) to get them all into balance with one another as well.

I'm bigger on the added items than I am on added creatures, as I'm using http://www.nexusmods.com/oblivion/mods/42780 overhaul which already alters creature spawns and adds some new ones.

My favorite non-overhaul item/creature adding mod is http://tesalliance.org/forums/index.php?/files/file/1318-wac-waalx-animals-creatures/ It not only adds creatures it adds a ton of great items (including an updated version of Waalx' Real Swords mods) to the game. WAC's robes are my all-time favorite robes for this game and his armors are great too. It also comes with a really interesting overhaul to the arena and Waalx' reworking of Crowded Roads, and several other optional add-ons.

Creatures: http://www.nexusmods.com/oblivion/mods/26634/? created by same author who did the Kvatch Rebuilt or WAC http://tesalliance.org/forums/index.php?/files/file/1318-wac-waalx-animals-creatures/ (requires a registered account)

Items: not sure which ones you're referring to... but if you want artifacts http://www.nexusmods.com/oblivion/mods/29931/? or new armors and weapons http://www.nexusmods.com/oblivion/mods/18417/? and http://www.nexusmods.com/oblivion/mods/18417/?

Edit: Those two above beat me to it.

Note: WAC tend to have compatibility issues with any other major overhauls out there because it was designed to be a standalone overhaul so be sure to drop other overhaul if you decide to try it. It's quite well made at least.

This is the latest version FYI: http://tesalliance.org/forums/index.php?/files/file/1283-martigens-monster-mod/ and yes it is compatible with Frans.

Many thanks to all of you for these quick and helpful responses! I'll investigate your recommendations.