Sarah is expecting her third child -- a boy! -- to join Winifred Frances "Winnie" and Harold Paschal "Harry".
My husband and I are expecting our third child next spring, and are seeking assistance with a name with British/Germanic origins. We adore strong, formal given names softened with a homespun nickname. We think it may be a bit much to have another child with the “ie or y” ending to a nickname.
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I love the bold choices of Winifred and Harold coupled with the sweet nicknames Winnie and Harry. Your list has so many great choices that it is very difficult to find better suggestions. George is certainly popular as a top 10 staple but you could always go for an unconventional nickname like Geordie or Jory.
Magnus – With the Roman grandeur of Maximus and gentlemanly charm of Rupert and Edmund, Magnus is strong and stylish name (it literally means "great, mighty"). As an added bonus, Magnus could have Max as a nickname, or the adorably homespun Gus.
Fergus / Augustus / Angus / Gustav – Speaking of lovely Gus, all three of these grand and fabulous names lend themselves effortlessly to this easy and friendly nickname.
Christopher – Robert, James, George, Philip, Charles... the natural addition is classic Christopher. Nicknames not only include the favourite Chris, but also the antique Kit (ala Marlowe and Harrington) and traditional vernacular Kester.
Benedict – Sleek, saintly and stylish, Benedict is Continentally appealing with a heritage much like that of Sebastian, Theodore, Valentine and Maximus. Ben is a classic go-to nickname, but I prefer the oh-so-stylishly medieval Ned.
Rufus – A kingly name with a solid yet quirky quality. Part Rupert, part Maximus.
Julian – A classic, solid and refined staple. Jules or Jude make for easygoing nicknames.
Gilbert – A smart Germanic name which was brought to Britain by the Normans and it became an established staple. Gil and (my favourite) Gib were preferred in the Middle Ages as short forms, but Bert(ie) also works.
Bertram – Another Norman-introduced Germanic name is dapper Bertram. Both Bert(ie) and Bram would work well as nicknames.
Leopold – A Germanic name meaning "strong man of the people" with princely British credentials and easy nickname of Leo.
Ranulf/Ranulph – A bold Germanic name derived from hraben "raven" and wolfa "wolf" (literally the same elements as Wolfram in reverse). Ralph and Rafe would make for excellent homely nicknames.
Bernard – The Norman French form of both a native Old English name and its Germanic cognate. A strong and solid name with lots of history but with the adorably friendly nickname Bernie.
Peregrine – A Late Latin name meaning traveller which has been in use in Britain since the 13th century when it was also used as a name for falcons. Nickname possibilities are numerous: Pippin (aka LoTR character Peregrin "Pippin" Took) , Pip, Perry, Piers/Peers and Iggy.
Alexander – A strong and heroic classic name with plenty of nicknames to choose from. Beyond Alex there is also Alec, Alick, Lex, Sandy and Xander. Also worth considering is the Scottish variant Alistair/Alasdair.
Honouring Gregory Allen:
Beyond Gregor, Gregory is a tricky one to to find variants for. The international variants include Grigor, Gregers, Gregorio (Goyo), Gregoire and Grigoriy, -- all of which are in a same ball park as Gregory and Gregor.
There are a few variants that offer a different sound. The Scottish diminutive form of Gregor is Greig. (which is pronounced GRAYG -- a very slightly longer vowel sound than Greg).
There are also the surname forms which derive from Gregory: Greer/Grier and Grix.
The most basic way to honour is to use Gregory as a middle name, but you could also use the same initials of G.A. -- George Alban or George Alistair for example.
I hope this has been of use. Best wishes for finding the perfect name.