This is really a question you should be asking whomever your Juniper reseller/partner would be, or else your local Juniper sales team.
Why not QFX5110-48S (or similar)? 4 x QSFP28 (native 100GE or 40GE) along with 48 x 1/10 Fiber GE. You'd need to use 1GE Copper SFP for 1GE copper, which adds to the cost, but appears to have everything you need, no?
This will provide you 10/40/100 GE. 100GE and 40GE are native, while to get 10GE you'll need a 4x10GE Optic along with a 4x10GE break-out cable. Those SKU Options for SMF and MMF are (optic 1st, cable second; cable comes in different lengths):
QSFP+ 40GBase-LR4 40 Gigabit Optics for up to 1km transmission over parallel SMF
QSFP+ 40GBase Optics, up to 10km Transmission on Parallel single mode (4X10GE LR up to 10km)
MTP to 4xLC pairs MMF passive breakout cable, 5m length
MTP to 4xLC pairs SMF passive breakout cable, 5m length
For 1GE, not sure if you need Copper or Fiber or both, but best and most cost effective would be to purchase a 1GE switch (EX2300?) which has 10GE uplink, connect to QFX5200 via 10GE to get your 1GE support.