For what you're looking at doing, I say it's hard to beat either the Sartek rechargeable EBL220 or UK's new Super Q LED.
I have a UK Q40 eLED+ that I use as a backup for caving(and will use it for diving in the tropics IF I ever make it down there again...my 12w Salvo would be a little obnoxious for night dives there
) and it's honestly a very good light. I also own an OMS Vega(older version, non K2) but if I were to buy another backup light right now it'd probably be another UK Q40 eLED. It's cheap, reliable as any, good burn-time and just about as bright as my Vega. That's why I think the Super Q would be a good light for you.....good company, good product, it's the Super Q is very bright for its size and rechargeable, and leaves you left over money to go buy TWO UK Q40's as backups, or even another Super Q and still be under $200. These would all be small, handy dandy lights.
Since there's a new generation of LED's being put out on the market, you could also pick up a pre-2009 Princeton Tec Shockwave/Miniwave for pretty cheap, or many different combos of Princeton Tec Shockwaves(new or old), UK C4 eLED's, or UK Super Q lights for under $200. Pistol grip lights are a pain in the ass to multitask with, however, and I found them quite annoying underwater so put that in your brain housing group for future reference. The first time I tried a can light I was hooked like a fat kid loves cake. Convienience/ease of use goes a long way over paper schematics of rated performance when you're multi-tasking. In my case, that's running lines. In others it's spearfishing. If you don't really ever run guidelines or spearfish or something, then the Shockwave/Miniwave and UK C4/C8 LED's deserve a hard look.
I wouldn't even consider the Salvo Rat or Halcyon Scout lines for your purposes. They're not bad lights, but there's definitely better for less $$.
Let us know what you choose!