There are many different opinions about this, all valid in their own right. Of the titanium stoves I've researched, I like the one of the versions that Seek Outside makes that still used a rectangular box shape:
Titanium Wood Stoves - Seek Outside
That said, I do not own one. I do have three sizes of the Kifaru stove to fit the tipitents I have. For me, I like a stove with a flat top and the four legs going down into the soil allows you to stabilize/level a stove in a way that several other designs do not. Are there lighter, perhaps more efficient stoves? Lighter?... definitely. More efficient?...apparently to some...but from what I've seen after a number of years using these lightweight stoves, and designing shelters around them, I personally think the utility is not as great on designs that don't incorporate the two features mentioned. Just me. Many will disagree.