One thing you can do is jazz up the intro and abstract to point out that you are for the first time applying technique X to field Y, and it fairly easily yields the solution to open problem Z. Thus the importance of the paper is not the difficulty of the proof, but the introduction of technique X. This sort of paper has the potential to be widely cited as other researchers in field Y start to use technique X, so I think a good journal is very appropriate.

What sort of conditions do you have in mind? Are you looking for an h-cobordism-type theorem for $3$-manifolds cobounding surfaces? The h-cobordism does hold in this case, which follows from the Poincare conjecture (=theorem).

@Alexander: Yes I agree that Duflo is much much harder than PBW.

Mike and Mike are different people!?

erratum is the singular form. :)

Thanks, the first paper was exactly the paper I was trying to remember.

@Samuel: Do you want an ideal triangulation? (Meaning vertices at infinity and edges geodesic.) That's a bit harder. Otherwise, yes you can just look at your manifold as a quotient space of a polyhedron and subdivide.

Can't you triangulate these dodecahedral manifolds by taking the central subdivision of each face, coning to the center, and then barycentrically subdividing?

See en.wikipedia.org/wiki/Topological_combinatorics and the references contained there.

I do to, but I've had some students complain that it doesn't have enough detail.

I agree that any paper is a bonus. Also, looking at my second comment, I did point out that it's probably too late for the OP to change his or her mind anyway.

@Sridhar: sorry, I just read this. Yes you are right that this is the fault of poor notation for the partial derivative, but the point still stands that naive cancellation is to be avoided without thinking through what it means.

The thing I don't like about Milnor's notes is that he scrupulously avoids talking about handles, always working directly with the Morse function.

A modular operad is basically an operad which you can plug into itself. The twisting is, I think, related to making the signs work out in the Feynman transform (graph complex). See GK's discussion on orientation.

Thanks for giving more complete references! Hope you are doing well, Sergey.