@Rocus
I’m going to assume from your description, your Eiffel Tower prints with a lean like the Tower of Pisa, not a banana with increasing curvature.
If you print with base and supports, the base “absorbs” the errors of calibration, non-planar surfaces, etc. As you prefer to print without base+supports, a printer calibrated using my method will print as closely to straight as one can get but I can tell you the build platforms are not uniformly flat (+/- 0.15mm concavity from edge to center on mine) so factor that in as well.
After calibration, a 2mm, small foot print base prints uniformly 1.98 - 2mm thick. Calibrating your printer this way will help when printing directly to the platform (no base) and void your warranty if they see finger prints inside the case! I’m working on a write up for the process and hope to post it to the Unofficial Wiki this week.
Also, leveling the silver case to the Form 1 is not useful to this issue however parallelising the build platform to the peel tray (the black metal frame under the vat) is critical.