Thanks. Will electric hydronic baseboards be a reasonable installation choice on their own, or do I need to couple them with underfloor heating?

"I'm concerned that with either of these solutions I'll have lots of drafty cold air coming off the windows"

I think you know it but the problem isn't with the heating, it's with the windows. Inefficient windows -- and they don't have to be leaky -- lead to drafts when warm air approaches the cool windows and falls (like warm air rises) resulting in the continuous (and unpleasant) circulation of air throughout the room. The floor heaters hide the problem but don't solve it and in a way that may be costly.

It doesn't matter how good your windows are; a wall of glass will be cold and cold air will drop off of a cold surface. Another option is forced air at the floor. All of the heating needs can typically be provided by perimeter baseboards.

@Seabornman: "It doesn't matter how good your windows are..."

I have no idea where you are getting this "information".

"Although windows have a significant annual energy impact, their biggest impact is on occupant comfort and on peak electricity and natural gas use. Comfort is a major concern in cold climates where poorly insulated windows create extreme radiant discomfort and generate cold drafts from air dropping across the surface of the glass—many building occupants report that it feels as if the windows are open or have very large edge gaps... Highly insulating and dynamic solar control technology solutions can solve these problems in residential and commercial buildings independent of climate..."*

"In cold climates, efficient windows minimize the gaps in temperature between the glass surface and the rest of the house. When this temperature gap is too large, cold air forms near windows. Because heat rises, these cold drafts drop to the floor, creating air-movement patterns that cause heat loss. Efficient windows prevent this problem..."**

*Pathway to Zero Energy Windows

**Efficient Windows Collaborative > Control Comfort

Since windows are a giant hole in a home’’s insulation, and struggle to even get to R-6, their tightness to air infiltration is secondary to them being a big radiator mechanism for heat transfer to the exterior. Which creates cold spots and drafts, regardless of how air tight they are. Because: physics. This is why Victorians used big heavy velvet doubled drapes to insulate the interior from the heat leaving out the windows.

@lomo: "Which creates cold spots and drafts, regardless of how air tight they are."

Nonsense. People build comfortable, passive houses using large, energy-efficient windows and don't have "cold spots and drafts". Even my 1980's condo no longer has "cold spots and drafts" since the old, wood windows were replaced with triple-pane, fiberglass windows.

@lomo: "Victorians used big heavy velvet doubled drapes to insulate the interior from the heat leaving out the windows"

Of course they did. They didn't have access to modern, efficient windows like we do. They also raised their beds high off the floor because the rooms were so cold. Do we still do that?