Oh OP, I really relate. We went through this after my gran passed, then again after my mum, and I can completely see how it makes you both nostalgic and suddenly very aware of your own legacy and future clutter.
Here's what helped me — maybe it'll help you too:
For your parents' things:
Medals / jewellery:
I picked one or two of each that actually had a story attached. The rest I either offered to family or donated (some charities take costume jewellery).
For medals, sometimes a little shadow box or framed display can make them more meaningful — rather than them sitting in a drawer quietly judging you.
Photos of unknown people:
You're absolutely right — we’re remembered for 1–3 generations, then people become “vintage sepia strangers.” I made peace with that.
I kept some of the most visually striking ones for an album called “Before Us” and scanned others, labelled "unknowns", and uploaded to a shared Google Drive. If cousins want to dive into ancestry stuff, it’s all there.
Wedding dress:
I kept mine (my mum’s was too far gone), but with hers, we took some photos of it, kept a little swatch of the lace and let it go. It was lovely but had no practical place in our lives.
Photos of your parents before you were born:
These are gems! Try to keep a few that capture them being silly, stylish, romantic, or just themselves. Even if you don’t know who they’re with, they tell a story.
I made a “before I existed” mini album — it’s quite sweet.
For your own house and future-proofing:
You’re spot on — it’s about balance. You don’t want your kids buried in boxes of “things Mum couldn’t let go of”, but at the same time, little mementos are lovely.
Here’s what I’ve done:
Personal keepsakes:
I made a “memory box” per child (just one plastic crate each). School drawings, funny letters, a baby outfit, a toy they loved. No more than that. They’ll have a sweet little time capsule when I’m gone (or just mildly embarrassed when I pull it out at 21).
Ongoing decluttering:
Label things! I now go round photos with post-its on the back — who’s who, where, when. That way, they’re not mysterious ghosts to my kids later.
I also review my "sentimental stash" once a year. If something no longer tugs at the heartstrings, it’s probably time for it to go.
And most importantly — tell your stories:
Keep a little journal or voice note log of family stories. Your children will treasure your voice and your words more than a hundred identical pictures of school assemblies and holidays.
You don't have to keep everything. You don’t have to toss it all either.
Keep the items that come with love and stories, let go of the anonymous or joyless. And in your own life, curate your sentimental bits with purpose — label, reduce, and make them meaningful, not overwhelming.
And be kind to yourself. Grief has many layers, and so does memory.