Wow sounds like great fun. Lavander and jasmine would need outdoor quality light probably 8 hours or more. Is there a floor or just dirt? Can the temp be controlled, under glass it will get very hot. Hibiscus would be an easy plant with lots of flowers. Some passion flowers are fragrant vines and pretty easy to grow. Is the greenhoust in full sun

Welcome to Gardenweb! I see from your profile that you are in Spain. I would love to see a picture of your conservatory if you feel like adding one to this discussion. How much space do you have in it?

Generally, plants grown outside in the sun for their flowers are usually unable to grow as well inside because there's so much less light inside. A conservatory should have much more light than inside a regular room in a house, but it's not possible to know from the info here so far if it is enough light for certain plants, or possibly too much for other plants (like ferns.) Determining how much light is available is the first step to selecting potential plants.

There's a reason why most books deal with indoor container gardening...that's what most people do.

That being said...

Interior Landscape Design, by Nelson Hammer
Foliage Plants for Decorating Indoors, by Virginnie F. and George A. Elbert

Then I'd check with the ASLA for any recommendations and with Timber Press for any current titles of interest.

Beyond that, you're going to have to extrapolate. What are the primary limiting factors of growing indoors? What are the great advantages of growing indoors? How does your particular site enhance or limit these factors, and/or what can you do change them?