I've looked through the other threads on FRA stopovers, but my questions is a little more specific and not really addressed. I'm really hoping some Frankfurt Foodie FTers can help

I arrive on a Friday morning at 9:15am with an onward (intra-Europe) flight at 3:20pm. That should leave me plenty of time to shower in the lounge, head into the city, have lunch, and return. The question is where. My criteria, from most to least important, are:

(1) Location: I'd like to leave 1.5 hours for lunch, so the restaurant needs to be relatively close to the train station. I'm not sure where exactly to draw the line, but I do know that I don't want either to worry about rushing the meal or to cut things too close getting back to FRA either.

(2) Cuisine: While I know there are lots of good European and non-European places in Frankfurt, I'm looking for German/Austrian food only. However, I don't eat pork, so any place I go would need to have some non-pork options. (I know, I know, some of the best German food is made of/with pork. What can I do?) So all-wurst joints are out.

(3) Wish List: I'd prefer somwhere new and interesting vs. old and famous; modern interpretations over classic presentations; someplace up and coming rather than quote-unquote "authentic"; someplace I can pair the food with good German wine; and a good location -- people watching, an attractive room, etc. -- where I could while away the time would be nice as well.

(4) Cost: I'd like to spend 30-40 Euros all-in, but I would go higher if the more the place fit my wish list in (3) above.

Thanks so much in advance for your ideas and suggestions! It's easy enough to find places near the train station, and I've looked at lists (on chowhound.com and elsewhere) of best Frankfurt restaurants, but it has been difficult to combine the two criteria into a meaningful set of choices.