What's the best way to automate server deployment without needing a domain?

I'm working on deploying servers for our customers, typically around 20 servers about 15-20 times a year, which totals around 500 server installations annually. Right now, our installation process isn't fully automated. We use HPE servers and configure iLO through their REST API, but there's some debate within my team about whether we should switch to HPE's "Intelligent Provisioning" tool, which helps by injecting a base driverset into Windows installations. The problem is, it takes way too long—over a day to install just 10 servers! With our limited 1GBit network and ISOs mounted over it, the process shouldn't be this slow. We've ruled out tools like Baramundi due to licensing issues, but we're open to purchasing software that doesn't bind to a server since we only do one-time installs and don't manage them post-shipping. I'm looking for ways to automate the installation process on Microsoft Server 2025 without requiring any domain or Azure connectivity. Ideally, I'd love to know if iPXE or HTTP boot are still viable options, and if I need to set up MDT and WDS. Here's what I want to automate: - Windows installation - Partitioning - Default user setup - Hostname assignment - NIC bonding with static IP address - Allowing Ansible connection Once the initial setup is complete, Ansible will take over. I'd like this workflow to work for VMs on Hyper-V as well, and I prefer a manual boot process or importing MAC addresses rather than full automation. Creating a custom ISO with HPE drivers would help, but their SPP is quite complicated. Any pointers would be greatly appreciated!