A super sharp, demagnetized razor (if you are cutting tape with aduio on it) and a precision splice block are key if you hope to ever have perfect edges that line up without gaps...after that it's mostly practice.
I find it easier to splice 2" tape right on top of my deck where the block is...than when I had to splice 1/4" tape...I guess it's a size thing.
But you know....I hardly ever splice tape anymore. I was never doing a lot of reel tape splices anyway, as I saw no need for them....mind you, I was the only one handling my tapes, so I just kept a log file of where stuff was on the tape, and used the counter to tell me when I was there. Also...I never sent out reels for any mixing/mastering...so again, no need to provide splices and all that.
Then of course, once I started dumping tape tracks into a DAW for edits and stuff about 17-18 years ago...I didn't even need to splice tape for the sake of editing anymore.
Also...sometimes I'll reuse a reel, and I hate when there are splices. I bought a bunch of used 2" reels when I got my MX-80 back in the springtime...and of course, a bunch of them had some splice(s), but in the pro studios where tapes move from one to another studio, from song to song or even track to track...the splices are almost required for speed/ease of continuity, and of course, all the calibration tones and well marked takes....etc.
What are the reasons you anticipate in your recording that will require splices...?
The most splicing I ever did was when making tape loops for my tape delay machine.

Buying the 16 foot loops wasn't cheap...so I just rolled my own. It was 1/4" tape...and you had to nail the splice so as not to keep getting
a thump/click when the loop came around. I threw away a bunch of loops in the beginning....
There's at least 2-3 guys here who could give you even better tips...as they probably did tape splicing regularly in their past.