I just gave it a quick try (played two levels) and I think it's worth finishing it. As far as I see there aren't that many action games where you drive around a tank, and the game seems to already be in a state where the real missing thing is "just" content (missions e.g.), so it shouldn't need to much work getting it polished up for a final release.

Sure, I noticed several things right from the start when playing these two levels that need work, but I'm sure most if it could be fixed very easily, so there should be no reason not to release this, so from my side : yes, finish it or maybe release the source and get some people from the community finish this, cause pascal games are currently very rare.

Here are some things I noticed on my first quick play that should be fixed :
- Widescreen resolutions. Cause 4:3 screens are very rare nowadays, and the game stretched to 16:9 looks bad.
- Audio levels. At default settings music is much too loud and I could barely hear the soundeffects. I think it should be the ohter way round
- Music. It doesn't fit the game, it should be more of a background-kind of music with a military touch.
- "Heavyness" of a tank. A tank is a heavy and sluggish vehicle. But the game lacks this feeling. Turret should move slower, firing frequency should be lowered, firing range should be enlarged.
- Armor system. It would add a lot to the gameplay in my eyes. So you'd have a front, back, left and right armor, each with it's own "health", so you'd have to watch your four sides instead of just having one health bar.

So if you decide to finish the game I hop this list will help a bit in getting it polished for release.