Complex sentence: Although still respecting the original foundations, the new structure was to reflect the prevailing late baroque style and 18th century aesthetic, of an imposing and ostentatious exterior accommodating a series of sumptuously furnished spaces within.
Split into simpler sentences: Although still respecting the original foundations, the new structure was to reflect the prevailing late barroque style and 18th century aesthetic. An imposing and ostentatious exterior accommodating a series of sumptuously furnished spaces within.