We did this to our 1960s 3 bed detached. House was long and thin ( still is) large living room to rear overlooking garden, galley kitchen in middle and dining room to front.
Front door and vestibule alongside dining room. we built 7 feet out into front garden, turned 7 feet of extension in front of dining room and dining room into new big kitchen, knocking through window that formed fron wall of house.
Velux windows in roof makes it very light and airy. where front door used to be also was new area of 6 feet and 7 feet, which squeezed in downstairs shower room with WC.
Old galley kitchen had walls into hall taken down to make new z shaped hall and split original kitchen in 2, making PC area and bookshelves, and put new wall in and door to make small utility for washing machine, dog, all the shoes and units for all that stuff you need sometimes but not in the kitchen. velux over new part of hall too, all bright.
I was scared it would make the house look odd, everyone here has side back to front extensions, but it looks okay! I can send you plans to see.