FIrst steps with Mellanox SN-2010 for a proxmox cluster

After we deployed our proxmox cluster (4 nodes with additional chrono on backup server), we quickly discovered that existing unifi switches were not up to the task. Overall this is a really nice (though sometimes frustrating) experience for me.

Lucky enough we came across two used SN-2010 at a customer installation and I have some questions that I struggle with (Mellanox is entirely new to me, as are ONIE related topics).

Q1: how I imagine it the setup would be the following:

VLAN 10: Cluster communication and Chrono L2 LACP two cables one per switch
VLAN 20: Storrage L2 LACP two cables one per switch
VLAN 30: Backup L2 LACP two cables one per switch

Both switches are connected with an additional VLAN directly on the 100gbe port with two cables.

Is that a feasible setup or am I misunderstanding anything?

Q2: Can the above setup be configured and maintained via WebGUI of Onyx?

Q3: If it can not be maintained via web, we need to get used to ssh configuration of switches anyway, which OS should I go with?