Only way to make it smaller without sacrificing video quality is to swap in lossy audio, but that'd only save you like 300MB an episode (maybe around 7GB total) at most. I'm sorry that you feel this is big, even though Part 1 is nearly half the size of UTW's release, but I don't do low-quality miniHD releases. Even USS's 720p release with lossy audio was only about 8GB less weighing in at about 22GB, while their 1080p with lossy audio was bigger than our release by almost 5GB (would have been roughly 13GB bigger with lossless audio).

So when you actually look into things, you'll see this release is one of the smallest versions available, while being dual-audio with flac. It comes in with an average of 1.28 GB an episode across 00-25 (33.4GB ÷ 26 episodes = 1.284 GB), and that's with three of them being 50 minutes long so the equivalent of 29 episodes and an OVA/Special at only 33GB isn't bad at all imo. I didn't think anyone worried about file size anymore with Gigabit internet and 4TB hard drives being so cheap.

However if AnimeTosho fetches this, then subtitles will be available as usual.

You can't, unless someone makes patches, but the patches would be at least 7GB (for all the English FLAC + subs + fonts)... So I doubt anyone would bother. Even if not in patches, you'd still need the same amount of data for just the audio tracks and subs and then you'd need to mux it all yourself. So you're just as well at downloading this from scratch cause you'd already be 1/4 of the way there.